METHOD 8327
PER- AND POLYFLUOROALKYL SUBSTANCES (PFAS^ USING EXTERNAL STANDARD
CALIBRATION AND MULTIPLE REACTION MONITORING (MRIVH LIQUID
CHROMATOGRAPHY/TANDEM MASS SPECTROMETRY (LC/MS/MS)
TABLE OF CONTENTS
I.0	SCOPE AND APPLICATION	3
2.0	SUMMARY OF METHOD	5
3.0	DEFINITIONS	6
4.0	INTERFERENCES	6
5.0	SAFETY	7
6.0	EQUIPMENT AND SUPPLIES	8
7.0	REAGENTS AND STANDARDS	9
8.0	SAMPLE COLLECTION, PRESERVATION, AND STORAGE	13
9.0	QUALITY CONTROL	14
10.0	CALIBRATION AND STANDARDIZATION	20
II.0	PROCEDURE	20
12.0	DATA ANALYSIS AND CALCULATIONS	26
13.0	METHOD PERFORMANCE	27
14.0	POLLUTION PREVENTION	27
15.0	WASTE MANAGEMENT	28
16.0	REFERENCES	28
17.0	TABLES, DIAGRAMS, FLOWCHARTS, AND VALIDATION DATA	29
TABLE 1 SUGGESTED LLOQ AND CALIBRATION RANGE	30
TABLE 2A LCS PERFORMANCE SUMMARY FROM MULTI-LABORATORY VALIDATION
STUDY	31
TABLE 2B LLOQ VERIFICATION PERFORMANCE FROM MULTI-LABORATORY
VALIDATION STUDY	33
TABLE 2C. RECOVERY AND PRECISION OF TARGET ANALYTES AND SURROGATES IN
MULTI-LABORATORY STUDY MATRICES PREPARED BY METHOD 35121	34
TABLE 3 RETENTION TIME (RT) AND MRM IONS	36
TABLE 4 PREPARATION OF CALIBRATION STANDARDS*	38
TABLE 5A EXAMPLE OF TERNARY GRADIENT CONDITIONS FOR LIQUID
CHROMATOGRAPHY	39
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TABLE 5B EXAMPLE OF BINARY GRADIENT CONDITIONS FOR LIQUID
CHROMATOGRAPHY	40
TABLE 5C INSTRUMENT CONDITIONS USED IN METHOD DEVELOPMENT	41
TABLE 6 EXAMPLES OF SURROGATES AND RECOMMENDED TARGET ANALYTE
ASSOCIATIONS	42
TABLE 7 QC SUMMARY	43
FIGURE 1 PFOS IN CALIBRATION STANDARD	44
FIGURE 2 PFOS IN GROUNDWATER SAMPLE	44
FIGURE 3 PFHxS IN CALIBRATION STANDARD	45
FIGURE 4 PFHxS IN GROUNDWATER SAMPLE	45
APPENDIX A - GLOSSARY	46
APPENDIX B (future Method 3512) - AQUEOUS SAMPLE PREPARATION	48
Disclaimer
SW-846 is not intended to be an analytical training manual. Therefore, method
procedures are written based on the assumption that they will be performed by analysts formally
trained in the basic principles of chemical analysis and in the use of the subject technology.
In addition, SW-846 methods, with the exception of required use for the analysis of
method-defined parameters, are intended to be guidance methods which contain general
information on how to perform an analytical procedure or technique, which a laboratory can use
as a basic starting point for generating its own detailed standard operating procedure (SOP),
either for its own general use or for a specific project application. Performance data included in
this method are for guidance purposes only and must not be used as absolute quality control
(QC) acceptance criteria for the purposes of laboratory QC or accreditation.
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1.0 SCOPE AND APPLICATION
This method covers the analysis of selected per- and polyfluoroalkyl substances (PFAS)
in prepared extracts of various matrices (e.g., waters and solids) by liquid
chromatography/tandem mass spectrometry (LC/MS/MS) analysis.
The 24 PFAS that have been evaluated with this method are provided below. The
suggested Lower Limit of Quantitation (LLOQ) and calibration ranges for these compounds
listed in Table 1 (Sec. 17.0) are based on the example calibration standards and spiking
solutions preparations described in Sec. 7. This method has been tested in reagent water,
surface water, groundwater, and wastewater matrices. Some precision and bias (P&B) data are
provided in Table 2 (Sec. 17.0).
Analvte

CAS RN*
PFAS sulfonic acids


Perfluoro-1-butanesulfonic acid (PFBS)

375-73-5
Perfluoro-1-pentanesulfonic acid (PFPeS)

2706-91-4
Perfluoro-1-hexanesulfonic acid (PFHxS)

355-46-4
Perfluoro-1-heptanesulfonic acid (PFHpS)

375-92-8
Perfluoro-1-octanesulfonic acid (PFOS)

1763-23-1
Perfluoro-1-nonanesulfonic acid (PFNS)

68259-12-1
Perfluoro-1-decanesulfonic acid (PFDS)

335-77-3
1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS)

757124-72-4
1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS)
#
27619-97-2
1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS)
#
39108-34-4
PFAS carboxvlic acids


Perfluorobutanoic acid (PFBA)
#
375-22-4
Perfluoropentanoic acid (PFPeA)
#
2706-90-3
Perfluorohexanoic acid (PFHxA)
#
307-24-4
Perfluoroheptanoic acid (PFHpA)

375-85-9
Perfluorooctanoic acid (PFOA)

335-67-1
Perfluorononanoic acid (PFNA)

375-95-1
Perfluorodecanoic acid (PFDA)

335-76-2
Perfluoroundecanoic acid (PFUdA)
#
2058-94-8
Perfluorododecanoic acid (PFDoA)
#
307-55-1
Perfluorotridecanoic acid (PFTrDA)
#
72629-94-8
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Analvte

CAS RN*
Perfluorotetradecanoic acid (PFTeDA)
#
376-06-7
PFAS sulfonamides and sulfonamidoacetic acids


N-ethylperfluoro-1-octanesulfonamidoacetic acid (N-EtFOSAA)
#
2991-50-6
N-methylperfluoro-1-octanesulfonamidoacetic acid (N-MeFOSAA)
#
2355-31-9
Perfluoro-1-octanesulfonamide (FOSA)

754-91-6
*Standards for some target analytes may consist of mixtures of structural
isomers; however, the Chemical Abstracts Service (CAS) Registry Number (RN) listed in
the table is for the normal-chain isomer. All CAS RNs in the above table are for the acid
form. Sulfonic acids in stock standard mixes are typically received as the sodium or
potassium salt form. CAS RNs for the salt form are not included.
# This analyte exhibits known difficulties with reproducibility, response, recovery,
stability, and/or chromatography that may reduce the overall quality or confidence in the
result when using this method. This analyte may require special care to ensure
analytical performance will meet the needs of the project and, where necessary, may
also require the use of appropriate data qualification. See Sec. 1.3 for specific
information regarding this analyte.
1.1	Prior to employing this method, analysts are advised to consult the base method
for each type of procedure that may be employed in the overall analysis (e.g., Methods 3500,
3600 and 8000) for additional information on QC procedures, development of QC acceptance
criteria, calculations, and general guidance. Analysts also should consult the disclaimer
statement at the front of the manual and the information in SW-846 Chapter Two for guidance
on the intended flexibility in the choice of methods, apparatus, materials, reagents, and
supplies; and (ii) the responsibilities of the analyst for demonstrating that the techniques
employed are appropriate for the analytes of interest, in the matrix of interest, and at the levels
of concern.
In addition, analysts and data users are advised that, except where explicitly specified in
a regulation, the use of SW-846 methods is not mandatory in response to Federal testing
requirements. The information contained in this method is provided by the U.S. Environmental
Protection Agency (EPA) as guidance to be used by the analyst and the regulated community in
making judgments necessary to generate results that meet the data quality objectives (DQOs)
for the intended application.
1.2	This method is restricted to use by, or under supervision of, appropriately
experienced and trained personnel. Each analyst must demonstrate the ability to generate
acceptable results with this method.
1.3	During method development the following compounds showed a potential for
reduced solubility either during standard preparation (resulting in low bias to calibration and high
recoveries for samples) or during sample preparation (resulting in low recoveries). Extra care
should be taken to ensure that the composition of the stock and intermediate standards
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maintain enough organic cosolvent, > 95%, to keep longer chain PFAS in solution. Sub-
sampling a container will also result in a loss of these compounds to the container walls, the
extent of which will be container dependent:
N-ethylperfluoro-1-octanesulfonamidoacetic acid (N-EtFOSAA)
N-methylperfluoro-1-octanesulfonamidoacetic acid (N-MeFOSAA)
Perfluorotetradecanoic acid (PFTeDA)
Perfluorotridecanoic acid (PFTrDA)
Perfluorododecanoic acid (PFDoA)
Perfluoroundecanoic acid (PFUdA)
During the multi-laboratory validation study, the following compounds may be difficult at low
concentrations due to due to lack of qualifier transitions and interferences:
Perfluorobutanoic acid (PFBA)
Perfluoropentanoic acid (PFPeA)
Perfluorohexanoic acid (PFHxA)
During the multi-laboratory validation study, the following compounds had quality control failures
at concentrations of 40 ng/L and below due to low response and/or high background:
Perfluorotridecanoic acid (PFTrDA)
N-ethylperfluoro-1-octanesulfonamidoacetic acid (N-EtFOSAA)
N-methylperfluoro-1-octanesulfonamidoacetic acid (N-MeFOSAA)
1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS)
1H, 1H, 2H, 2H-perfluorooctcane sulfonic acid (6:2 FTS)
During the multi-laboratory validation study, the following had frequent QC failures for
calibration, sample preparation QC, high background, and/or analytical enhancement:
1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS)
1H, 1H, 2H, 2H-perfluoro-1-[1,2-13C2] octanesulfonic acid (M2-6:2 FTS)
For all the # indicated compounds a higher concentration range than the 5 to 200 ng/L used in
the multi-laboratory study may be required to achieve data quality objectives.
2.0 SUMMARY OF METHOD
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2.1	Samples are prepared using an appropriate sample preparation method (e.g.,
dilution of water samples using Method 3512 in Appendix B, extraction of solid samples using
Method TBD) and, if necessary, an appropriate cleanup procedure (TBD). For Method 3512
water samples are diluted 1:1 with methanol, filtered, and acetic acid (0.1% by volume) is added
to adjust pH to ~3 - 4. Acetic acid is added primarily because it improved sensitivity for some
target analytes. Solids - TBD. Samples are then analyzed by LC/MS/MS using external
standard calibration.
2.2	Target compounds are identified by comparing multiple reaction monitoring
(MRM) transitions in the sample to MRM transitions in the standards (Table 3). The retention
time (RT) and qualifier ion ratio (if available) are compared to a mid-level standard to support
qualitative identification. Target compounds are quantitated based on the response of their
quantifier MRM transitions utilizing external standard calibration.
3.0 DEFINITIONS
Refer to SW-846 Chapter One and the manufacturer's instructions for definitions that
may be relevant to this procedure. See Glossary (Appendix A) for relevant terms and
acronyms.
4.0 INTERFERENCES
4.1	In order to avoid compromising data quality, contamination of the analytical
system by PFAS from the laboratory must be reduced to the lowest practical level. Method
blanks (MBs) and reagent blanks (RBs) are prepared and analyzed with all samples and are
used to demonstrate that laboratory supplies and preparation and analysis steps do not
introduce interferences or PFAS artifacts at levels that would bias quantitation, especially near
the lower limit of quantitation (LLOQ), or prevent the proper identification and integration of
target analytes. Careful selection of reagents and consumables is necessary because even low
levels of PFAS contamination may alter the precision and bias of the method as background
introduced by these materials (and variability thereof) is cumulative. See Sec. 9.5 for MB and
RB criteria. Refer to each method to be used for specific guidance on QC procedures and to
SW-846 Chapter Four for general guidance on glassware cleaning.
4.2	Refer to Methods 3500, 3600 and 8000 for discussions of interferences. Matrix
interferences can be caused by contaminants from the sample, sampling devices, or storage
containers. The extent of matrix interferences will vary considerably from sample source to
sample source, depending upon variations of the sample matrix.
4.3	The following are procedures employed to prevent or minimize problems with
measurement precision and bias.
4.3.1	All solvents should be of pesticide residue purity or higher (or preferably
LC/MS grade) to minimize interference problems.
4.3.2	PFAS contamination has been found in reagents, glassware, tubing,
polytetrafluoroethylene (PTFE) LC vial caps, aluminum foil, glass disposable pipettes,
filters, degassers, and other apparatus that release fluorinated compounds. All
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supplies and reagents should be verified prior to use. If found, measures should be
taken to remove the contamination, if possible, or find other suppliers or materials to use
that meet method or project criteria.
4.3.3	The LC system used should have components replaced, where possible,
with materials known to not contain PFAS target analytes of interest.
4.3.4	During method development, loss of some PFAS target analytes was
observed during storage of standard solutions in 50:50 methanol-water containing 0.1%
acetic acid in glass containers. Plastic containers (polypropylene or high density
polyethylene [HDPE]) are recommended to be used for preparation and storage of
samples and standards. Glass autosampler vials have been successfully used for
analysis of standards and samples in addition to plastic containers.
4.3.5	Polyethylene LC vial caps are recommended. Alternate materials may be
used if the blank criteria in Sec. 9.5 are met. PTFE lined caps should not be used.
4.3.6	Polyethylene disposable pipettes are recommended. Alternate materials
may be used if the blank criteria in Sec. 9.5 are met. When a new batch of disposable
pipettes is received, at least one should be checked for release of target analytes or
interferences.
4.3.7	Degassers are important to continuous LC operation and are most
commonly made of fluorinated polymers. To enable use, an isolator column should be
placed after the pump mixer and before the sample injection valve to prevent
contamination. The isolator column delays the contaminants to the analytical column and
must be located in the gradient flowpath.
4.3.8	If labware is re-used, the procedure described for labware cleaning (Sec.
6.2.4) should be followed to minimize risk of contamination. The blank criteria in Sec. 9.5
can be used as a guideline for evaluating cleanliness.
4.4 Where measured analyte concentrations are suspected of being high-bias and/or
false positive results due to contamination, the laboratory should inform the data user of any
suspected data quality issues.
5.0 SAFETY
5.1	This method does not address all safety issues associated with its use. The
laboratory is responsible for maintaining a safe work environment and a current awareness file
of U.S. Occupational Safety and Health Administration (OSHA) regulations regarding the safe
handling of the chemicals specified in this method. A reference file of safety data sheets
(SDSs) must be available to all personnel involved in these analyses.
5.2	Users of this method should operate a formal safety program.
5.3	The toxicity and carcinogenicity of each reagent used in this method has not
been precisely defined; however, each chemical compound is treated as a health hazard.
Exposure to these chemicals should be reduced to the lowest possible level and the appropriate
personal protective equipment (PPE) should be utilized. Review SDSs for specific physical and
health hazards including appropriate PPE to be used. SDSs can be accessed at multiple
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locations (e.g., www.siqmaaldrich.com,www.well-labs.com, and www.isotope.com).
6.0 EQUIPMENT AND SUPPLIES
The mention of trade names or commercial products in this method is for illustrative
purposes only and does not constitute an EPA endorsement or exclusive recommendation for
use. The products and instrument settings cited in SW-846 methods represent those used
during method development or subsequently evaluated by the Agency. Glassware, reagents,
supplies, equipment, and settings other than those listed in this method may be employed
provided that method performance appropriate for the intended application has been
demonstrated and documented. This section does not list all common laboratory glassware
(e.g., beakers and flasks) that might be used.
6.1 Equipment
6.1.1	Liquid chromatograph (LC) system: An ultraperformance liquid
chromatograph (UPLC) with stainless steel flow through needle design was used to
generate data during method development (PEEK needles may not puncture
polyethylene caps; pre-slitting of caps is not allowed).
6.1.2	Analytical columns: The following were used to generate data during
method development; other columns may be used, provided that method performance is
appropriate for the application:
6.1.2.1	Acquity UPLC® CSHTM Phenyl-Hexyl, 2.1 x 100 mm and 1.7
|jm particle size (Waters part no. 186005407)
6.1.2.2	ZORBAX RRHD Stable Bond C18, 2.1 x 100 mm and 1.8 |jm
particle size (Agilent part no. 858700-902)
6.1.2.3	Accucore RP 2.1 x 100 mm and 2.6 |jm particle size (Thermo
part no. 17626-102130)
6.1.2.4	Shim-pack SP-C18, 2.1 x 150 mm and 2.7 |jm particle size
(Shimadzu part no. 227-32003-04)
6.1.3	Isolator column:
6.1.3.1	XBridge BEH C18, 2.1 x50 mm and 3.5 |jm particle size (Waters
part no. 186003021)
6.1.3.2	ZORBAX RRHD Eclipse Plus C18, 50 x 3.0 mm, 1.8 |jm (Agilent
part no. 959757-302)
6.1.3.3	BDS Hypersil™C18, 2.1 x 50 mm and 5 |jm particle size
(Thermo part no. 28105-052130)
6.1.3.4	Shim-pack XR-ODS II, 2 x 75mm and 2.2 |jm particle size
(Shimadzu part no. 228-41605-93)
6.1.4	Mass Spectrometer (MS) System: An MS capable of multiple reaction
monitoring (MRM) analysis with fast enough cycle time to obtain at least ten scans over
a peak is needed with adequate sensitivity.
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6.2 Support Equipment and Supplies
6.2.1	Adjustable volume pipettes, 10-|jL, 20-|jL, 100-|jL, 200-|jL, and 1000-|jL,
5-mL, and 10-mL.
6.2.2	Analytical balance, capable of weighing to 0.01 g
6.2.3	Sample containers and miscellaneous supplies; all supplies should meet
blank criteria in Sec. 9.5 where practical.
6.2.3.1	Vials: 2-mL autosampler vials, HDPE, polypropylene or silanized
glass
6.2.3.2	Polyethylene autosampler vial caps (Waters Catalog #
186004169)
6.2.3.3	10- to 25-mL filter-adaptable HDPE, polypropylene or glass
syringes with luer lock adapters (rubber surfaces should not be used).
6.2.3.4	50-mL polypropylene tubes (BD Falcon, Catalog # 352098)
6.2.3.5	15-mL polypropylene tubes (BD Falcon, Catalog # 352097); use
pre-weighed tubes for collection of field samples and field QC
6.2.3.6	Polyethylene disposable pipettes (SEDI-PETTM PI PET, Source
- Samco Scientific, part no. 252 or equivalent)
6.2.3.7	Pipette tips: polypropylene pipette of various sizes (Eppendorf,
Catalog #s 022491997, 022492080, 022491954, 022491946, and 022491512)
6.2.3.8	Acrodisc GxF/0.2|jm GHP or equivalent membrane syringe
driven filter unit. Filters must be cleaned prior to use. A suggested protocol is to
rinse each filter with 2 x10 ml_ acetonitrile and then 2 x10 ml_ methanol prior to
use. Other protocols may be appropriate if PFAS contamination is removed or
reduced to levels appropriate for the project.
6.2.4	Reusable labware cleaning instructions - If labware is re-used it should
be washed in hot water with detergent such as powdered Alconox, Deto-Jet, Luminox, or
Citrojet, rinsed in hot water and rinsed with distilled water. All glassware is subsequently
rinsed with organic solvent(s) such as acetone, methanol, and acetonitrile.
7.0 REAGENTS AND STANDARDS
7.1 Reagent-grade or pesticide grade chemicals, at a minimum, should be used in all
tests. Unless otherwise indicated, all reagents should conform to the specifications of the
Committee on Analytical Reagents of the American Chemical Society, where specifications are
available. Other grades may be used, provided the reagent is of sufficiently high purity to permit
its use without lessening the accuracy of the determination. All reagents should be verified prior
to use to ensure the MB criteria in Sec. 9.5 can be met.
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7.2	Reagent water: All references to water in this method refer to reagent water
unless otherwise specified. Reagent water from in-house Dl systems will likely require
additional polishing with a point-of-use water purification system to meet blank requirements
(Sec. 9.5). The user is cautioned to check for PFAS addition from these systems (free from
fluoropolymers). Some bottled HPLC-grade water has been shown to contain PFAS.
7.3	Reagents and Gases: Items shown are for informational purpose only; equivalent
reagents and standards may be used. All reagents and solvents should be of pesticide residue
purity or higher to minimize interference problems, preferably LC/MS grade or equivalent.
7.3.1	Acetonitrile, C2H3N (CAS RN 75-05-8)
7.3.2	Ultrapure argon and nitrogen
7.3.3	Methanol, CH3OH (CAS RN 67-56-1)
7.3.4	Isopropyl alcohol, C3H80 (CAS RN 67-63-0)
7.3.5	Ammonium hydroxide, NH4OH (CAS RN 1336-21-6), 28-30%
7.3.6	Ammonium acetate, C2H7NO2 (CAS RN 631-61-8), neat
7.3.7	Glacial acetic acid, CH3COOH (CAS RN 64-19-7)
7.3.8	PFAS target compounds stock standards:
Solutions may be purchased as certified solutions or prepared from pure standard
materials. Commercially prepared stock standards may be used at any concentration if they are
certified by an accredited supplier or third party. For standards prepared from neat materials,
the weight may be used without correction to calculate the concentration of the stock standard
when standard compound purity is assayed to be 98% or greater. Use manufacturer's expiration
date for purchased prepared standards.
For the multi-laboratory validation study, a mixture of all 24 target analytes listed in Table
1 was obtained from Wellington Laboratories (Catalog # PFAC-24PAR, containing each target
analyte at a nominal concentration of 2000 ng/mL in MeOH). Sulfonic acids in this mixture were
prepared from salts, and some had certified concentrations of both straight-chain and branched
isomers.
7.3.9	PFAS Surrogates: An isotopically-labeled surrogate is recommended to
be included for each target analyte. If an isotopically labeled surrogate of sufficient purity
cannot be obtained, target analytes should be associated with surrogates that are as
chemically similar as possible. For the multi-laboratory validation study, a mixture of 19
isotopically labeled surrogates was obtained from Wellington Laboratories (Catalog #
MPFAC-24ES), containing each surrogate at a nominal concentration of 1000 ng/mL in
methanol. See Table 6 for the surrogate list and the suggested target associations.
7.4	Standard solutions - All standards must be kept away from PFAS-containing
packaging and materials used in preparation and storage. To prevent standard solutions from
degrading, all standard solutions should be stored at <6°C in the refrigerator. Standards must be
brought to room temperature and vortexed prior to use. Expiration date for standards prepared
from neat materials is one year from the time prepared or manufacturer's expiration date,
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whichever is shorter. The spiking standards and surrogates can be used for more than one
year if they fall within ±20% of the expected concentration compared to a freshly opened stock.
The suggested instructions for the preparation of calibration standard solutions and
surrogates and target compounds spiking solutions are listed below. Different concentrations
may be used depending on the sensitivity of the instrument, response of quantifier/qualifier,
calibration range used, or needs of the project. All intermediate stocks and spiking solutions
should be prepared in 95:5 acetonitrile-water using calibrated automatic pipettes with
polypropylene tips. Standard solutions should be prepared and stored in HDPE or
polypropylene containers. Alternate solvents (e.g. 96:4 MeOH-water) may be used provided
that method performance is not adversely affected (esterification in MeOH solutions is known to
occur; binding of longer chain PFAS to surfaces can occur at lower proportions of organic co-
solvent).
The following sections have suggested spiking concentrations for 5 ml_ water samples
from Method 3512 (Appendix B). Spiking amounts and concentrations should be adjusted as
needed if other volumes/weights or other preparatory methods are used.
7.4.1	PFAS surrogates spiking solution - Isotopically-labeled PFAS surrogates
(Sec. 7.3.9) are added to samples prior to preparation. Addition of 40 |jL of a 20 ng/mL
surrogates spiking solution to a 5 ml_ water sample would result in surrogate
concentrations of 160 ng/L.
Example preparation of surrogates spiking solution: A 200 |jL aliquot of a stock
PFAS surrogate mix at 1000 ng/mL concentration brought to 10 ml_ with 95:5
acetonitrile- water produces a solution at 20 ng/mL concentration.
7.4.2	Matrix spike/matrix spike duplicate (MS/MSD) and laboratory control
sample (LCS) spiking solution - PFAS target analytes (Sec. 7.3.8) are added to
MS/MSD and LCS samples prior to preparation, at a concentration near the mid-point
calibration standard after all preparation steps are completed. Addition of 40 |jL of a 20
ng/mL (nom.) MS/MSD and LCS target compounds spiking solution to a 5 mL water
sample would result in target analyte concentrations of 160 ng/L.
Example preparation of a MS/MSD and LCS target compounds spiking solution:
A 100 |jL aliquot of a stock PFAS target mix at 2000 ng/mL concentration brought to 10
mL with 95:5 acetonitrile-water produces a solution at 20 ng/mL concentration (nom.).
7.4.3	LLOQ verification spiking solution - PFAS target analytes (Sec. 7.3.8) are
added to LLOQ verification QC samples prior to preparation, at a concentration near the
LLOQ (i.e., 1/4 to 2X the laboratory's established LLOQ; See Sec. 9.9). For example, an
LLOQ verification QC sample can be prepared by spiking 25 |jL of target compounds
spiking solution at 2 ng/mL (nom.) into a 5 mL reagent water sample, resulting in target
analyte concentrations of 10 ng/L.
Example preparation of an LLOQ verification spiking solution: A 10 |jL aliquot of
a stock PFAS target mix at 2000 ng/mL concentration diluted to a final volume of 10 mL
with 95:5 acetonitrile-water produces a solution at 2 ng/mL concentration (nom.).
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7.4.4 Calibration standards - Two types of calibration standards are used for
this method: standards made from the primary source for ICAL and continuing
calibration verification (CCV), and standards made from a second source for initial
calibration verification (ICV). When using premixed certified solutions, store according to
the manufacturer's documented holding time and storage temperature
recommendations.
NOTE: Some PFAS analytes have both linear and branched isomers present in
commercially available standards (e.g., PFHxS, PFOS, N-MeFOSAA and N-
EtFOSAA).
7.4.4.1 ICAL: ICAL standards must be prepared at a minimum of five
different concentrations and are recommended to be prepared using the target
and surrogates spiking solutions in Sees. 7.4.1 and 7.4.2, or from dilutions of the
calibration standards stock described below. Include a minimum of five different
concentrations in the calibration for a linear (first-order) calibration model and six
different concentrations for a quadratic (second-order) model with the low
standard at or below the LLOQ (see Sec. 9.9 and Method 8000). At least one of
the calibration standards should correspond to a sample concentration at or
below that necessary to meet the DQOs of the project. The remaining standards
should correspond to the range of concentrations found in actual samples but
should not exceed the working range of the LC/MS/MS system. Each standard
and/or series of calibration standards prepared at a given concentration should
contain all the desired project-specific target analytes for which qualitative and
quantitative results are to be reported by this method.
Table 4 contains suggested calibration levels that were used during
validation of this method. Other concentrations or fewer standards may be used
depending on the needs of the project or sensitivity of the LC/MS/MS system. A
primary dilution standard (PDS) at 200 ng/L can be prepared by adding 100 |jL of
the surrogate spike at 20 ng/mL (Sec. 7.4.1) and 100 |jL of the PFAS target
compounds spike at 20 ng/mL (Sec. 7.4.2) and bringing to 10 mL with a 50:50
methanol-water solution containing 0.1% acetic acid (e.g., 10 uL glacial acetic
acid into 10 mL). The PDS can be used to prepare lower concentration ICAL
standards, e.g., 5 ng/L - 150 ng/L (Table 4) by diluting aliquots of the PDS with
appropriate volumes of 50:50 methanol-water containing 0.1% acetic acid.
NOTE: Calibration standards should not be reused once the cap is pierced
unless the vial is immediately recapped. Volatile losses can occur rapidly
because punctures of polyethylene caps leave large holes, and there is
no septum to mitigate losses.
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7.4.4.2	ICV: Second source standards for ICV must be prepared using
source materials from a second manufacturer or from a manufacturer's batch
prepared independently from the batch used for calibration. A second lot number
from the same manufacturer may be adequate to meet this requirement. Target
analytes in the ICV are recommended to be prepared at concentrations near the
mid-point of the calibration range. The standard must contain all calibrated target
analytes that will be reported for the project, if readily available.
7.4.4.3	Continuing calibration verification (CCV): CCV standards should
be prepared in the same manner as ICAL standards at concentrations near the
middle of the calibration range.
NOTE: It may be useful to prepare CCV standards at larger volumes and aliquot into
multiple autosampler vials so individual autosampler vials do not have to be
reused.
8.0 SAMPLE COLLECTION, PRESERVATION, AND STORAGE
Sample collection, preservation, and storage requirements may vary by EPA program
and may be specified in a regulation or project planning document that requires compliance
monitoring for a given contaminant. Where such requirements are specified in the regulation,
follow those requirements. In the absence of specific regulatory requirements, use the following
information as guidance in determining the sample collection, preservation, and storage
requirements.
8.1 Sample collection criteria - Grab samples are collected in high density
polyethylene (HDPE) or polypropylene containers. PTFE containers and contact surfaces with
PTFE must be avoided. Depending on the needs of the project, field blanks may be required
and must follow recommended PFAS sampling practices, where available. The samplers
should acquire pre-verified reagent water and bottles from the analytical laboratory for preparing
field blanks, where practical.
Surface binding of target compounds in water to collection containers is known to occur.
If possible, volumes collected for water samples should match volumes consumed in the
laboratory's preparation procedure (e.g., for Method 3512, collect 5 mL of sample in 15 mL
container to allow volume for the 1:1 dilution in the original container). The laboratory must
prepare the entire sample. Each field sample and QC sample must be collected in its own
container, including field blanks, MS/MSDs, and duplicates.
NOTE: REMOVING AN ALIQUOT OF WATER FROM A CONTAINER PRIOR TO ADDITION
OF ORGANIC SOLVENT IS NOT RECOMMENDED AND CAN RESULT IN
SIGNIFICANT LOSS OF LONGER-CHAIN PFAS TARGETS (e.g., carboxylic acids >C9,
sulfonic acids >C?). Water samples and sample extracts containing significant amounts
of water may only be transferred to additional containers if 50% organic co-solvent
content is achieved prior to transfer. Otherwise, quantitative transfer can be achieved
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by solvent-rinsing the empty container with methanol. Refer to Sec. 11.1.1 for more
details.
Conventional laboratory practices involving chain of custody, field sampling, lab custody
beginning with receipt and transfer custody, and sampling protocols should be followed. Extra
samples must be collected in order to analyze duplicate and matrix spike samples for quality
assurance (QA) and QC purposes.
8.2 Sample preservation and storage - All samples are iced or refrigerated at <6 °C
from the time of collection until sample analysis. In the laboratory, samples and sample extracts
should be stored in the refrigerator at <6 °C while not being analyzed. Formal holding times
have not yet been established for these analytes in various matrices. Based on an EPA
preliminary holding time study, a 28-day limit from sample collection to preparation of solids or
waters, and a 30-day limit from preparation to analysis of sample extracts may be used as a
guide until a more formal study is completed.
NOTE: Freezing samples can prevent losses and degradation of some target and non-
target PFAS into other PFAS target analytes. See Sec. 16.0, Reference 7.
9.0 QUALITY CONTROL
9.1	General guidance - Refer to SW-846 Chapter One for guidance on quality
assurance (QA) and QC protocols. When inconsistencies exist between QC guidelines,
method-specific QC criteria take precedence over both technique-specific criteria and Chapter
One criteria; technique-specific QC criteria take precedence over Chapter One criteria. Any
effort involving collection of analytical data should include development of a structured and
systematic planning document, such as a quality assurance project plan (QAPP) or a sampling
and analysis plan (SAP), which translates project objectives and specifications into directions for
those implementing the project and assess the results.
Each laboratory should maintain a formal QA program. The laboratory should also
maintain records to document the quality of the data generated. Development of in-house QC
limits for each method is encouraged. All data sheets and QC data should be maintained for
reference or inspection.
9.2	Refer to Method 8000 for specific determinative method QC procedures. Refer
to Method 3500 and 3600 for QC procedures to ensure the proper operation of the various
sample preparation and cleanup techniques. Any more specific QC procedures provided in this
method will supersede those noted in Methods 3500, 3600 or 8000.
9.3	QC procedures necessary to evaluate the LC system operation are found in
Method 8000 and include evaluation of RT windows, calibration verification, and
chromatographic analysis of samples.
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9.4	Initial demonstration of proficiency (I DP) - An I DP must be performed by the
laboratory prior to independently running an analytical method and should be repeated if other
changes occur (e.g., significant change in procedure, change in personnel). Refer to Method
8000 Sec. 9.0 for additional information regarding instrument, procedure, and analyst IDPs. An
I DP must consist of replicate reference samples from each sample preparation and
determinative method combination utilized by generating data of acceptable precision and bias
for target analytes in a clean reference matrix taken through the entire preparation and analysis.
If an autosampler is used to perform sample dilutions, prior to use, the laboratory should
demonstrate that those dilutions are equivalent to that achieved by an experienced analyst
performing manual dilutions.
For an I DP study, at least 4 samples containing all the PFAS and surrogates at or near
the midpoint of the calibration range must be analyzed as replicates. These samples are then
analyzed according to the method described in Method 8000 Sec. 9.0. Preliminary precision
and bias (P&B) acceptance criteria are 30% (RSD) and 70-130% (recovery).
9.5	Blanks
9.5.1	Before processing any samples, the analyst must demonstrate through the
analysis of a MB or RB that equipment and reagents are free from contaminants and
interferences. If a peak is found in the blank that would prevent the identification or bias
the measurement of an analyte, the analyst should determine the source of the
contaminant peak and eliminate it, if possible. As a continuing check, each time a batch
of samples is prepared and analyzed, and when there is a change in reagents, an
additional MB must be prepared and analyzed for the compounds of interest as a
safeguard against chronic laboratory contamination. MBs and field blanks must be
carried through all stages of sample preparation and analysis. At least one MB or RB
must be analyzed on every instrument after calibration standard(s) and prior to the
analysis of any samples.
9.5.2	Blanks are generally considered to be acceptable if target analyte
concentrations are less than one half the LLOQ or are less than project-specific
requirements. Blanks may contain analyte concentrations greater than acceptance limits
if the associated samples in the batch are unaffected (i.e., targets are not present in
samples or sample concentrations/responses are >10X the blank). Other criteria may be
used depending on the needs of the project.
9.5.3	If an analyte of interest is found in a sample in the batch near a
concentration confirmed in the blank (refer to Sec. 9.5.2), the presence and/or
concentration of that analyte should be considered suspect and may require
qualification. Samples may require re-extraction and/or re-analysis if the blanks do not
meet laboratory-established or project-specific criteria. Re-extraction and/or re-analysis
is not necessary if the analyte concentration falls well below the action or regulatory limit
or if the analyte is deemed not important for the project.
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9.5.4	When new reagents or chemicals are received, the laboratory should
monitor the blanks associated with samples for any signs of contamination. It may be
necessary to test every new batch of reagents or chemicals prior to sample preparation
as PFAS contamination is common. If reagents are changed during a preparation batch,
separate blanks should be prepared for each set of reagents.
9.5.5	The laboratory should not subtract the results of the MB from those of any
associated samples. Such "blank subtraction" may lead to negative sample results. If
the MB results do not meet the project-specific acceptance criteria and reanalysis is not
practical, then the data user should be provided with the sample results, the MB results,
and a discussion of the corrective actions undertaken by the laboratory.
9.5.6	At least one MB for every 20 field samples must be prepared in reagent
water to investigate for PFAS contamination throughout sample preparation, extraction,
and analysis.
Note: More than one MB or RB may be needed to evaluate for commonly
observed laboratory contaminants (e.g., 6:2 FTS) or for applications in
which very low levels (i.e., at or near the LLOQ) are of interest.
9.5.7	One RB is prepared for each day of analysis with a 50:50 methanol-water
solution containing 0.1% acetic to investigate for system/laboratory contamination.
PFAS contamination at low levels is common in laboratory supplies and equipment. The
50:50 methanol-water solution containing 0.1% acetic acid is analyzed to help determine
the source of contamination, if present.
9.6 Sample QC for preparation and analysis - The laboratory must also have
procedures for documenting the effect of the matrix on method performance (precision, bias,
sensitivity). At a minimum, this must include the analysis of a MB and LCS, and where
practical, an MS/MSD or MS/duplicate in each preparation batch, as well as monitoring the
recovery of surrogates. Any MBs, LCSs, MS/MSDs, and duplicate samples should be subjected
to the same analytical procedures (Sec. 11.0) as those used on actual samples.
9.6.1 Matrix Spikes/Duplicates - Documenting the effect of the matrix should
include the analysis of at least one MS and one duplicate unspiked sample or one
MS/MSD pair. The decision on whether to prepare and analyze duplicate samples or a
MS/MSD must be based on knowledge of the samples in the sample batch. If samples
are expected to contain target analytes, laboratories may use an MS and a duplicate
analysis of an unspiked field sample. If samples are not expected to contain target
analytes, then laboratories should use a MS/MSD pair. The preliminary acceptance
criteria are 70-130%. Statistically-derived acceptance limits or project defined
acceptance limits may be necessary for targets as 70-130% default limits may be too
narrow in some matrices. Consult Method 8000 for information on developing
acceptance criteria for the MS/MSD.
9.6.1.1 When required and sufficient sample is available, an MS/MSD
(Sec. 11.1.5) are prepared for each matrix at a frequency of at least one
MS/MSD pair for every 20 field samples to investigate for matrix interferences.
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9.6.1.2 As part of a QC program, spike accuracy for each matrix is
monitored. Bias is estimated from the recovery of spiked analytes from the
matrix of interest. Laboratory performance in a clean matrix is estimated from
the recovery of analytes in the LCS. Calculate the recovery of each spiked
analyte in the MS, MSD (if performed), and LCS according to the following
formula.
Cs = Measured concentration of spiked sample aliquot
Cu = Measured concentration of unspiked sample aliquot (use 0 for LCS)
Cn = Nominal (theoretical) concentration increase that results from
spiking the sample, or the nominal concentration of the spiked aliquot (for
LCS).
NOTE: MS/MSD recoveries may not be meaningful if the amount of analyte in
the sample is large relative to the amount spiked.
9.6.2	LCS - At least one LCS must be prepared with each batch of 20 or fewer
field samples. The LCS consists of an aliquot of a clean (control) matrix similar to the
sample matrix and of the same weight or volume, like the MB. The LCS is spiked with
the same analytes and at the same concentrations as the MS/MSD, when appropriate,
and is taken through all sample preparation steps. When the results of the MS/MSD
analysis indicate a potential problem due to the sample matrix itself, the LCS results are
used to verify that the laboratory can perform the analysis in a clean matrix. The
preliminary acceptance criteria are 70-130%. Statistically-derived acceptance limits or
project defined acceptance limits may be necessary for some targets, including PFTriA,
PFBA, and 6:2 FTS, as 70-130% default limits may be too narrow. See Sec. 9.6.1.2 for
recovery calculation. Consult Method 8000 for information on developing acceptance
criteria for the LCS.
9.6.3	A duplicate sample or MSD is analyzed with every batch of 20 field
samples, where available. The relative percent difference (RPD) between the sample
and duplicate or MS and MSD should be less than 30%. A laboratory control sample
duplicate (LCSD) may be used to demonstrate precision in the batch if extra field sample
containers are not received for performing duplicates or MSD.
Calculate the relative percent difference (%RPD) between the duplicates using
the following equation:
(Q - Cu)
Recovery = %R =	-—- x 100
where:
RPD =
X 100
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where:
C1 =Measured concentration of first sample aliquot
C2 =Measured concentration of second sample aliquot.
9.6.4 Surrogate recoveries - Surrogates are added to all field samples and
associated QC samples as described in Sec. 11. The isotopically-labeled surrogates
should represent the unlabeled native analytes where available. See Method 8000 for
information on evaluating surrogate data and developing and updating surrogate limits.
Procedures for evaluating recovery of multiple surrogates and associated corrective
actions should be defined in the laboratory's SOP or in project planning documents (e.g.,
QAPP, SAP). Preliminary acceptance criteria are 70-130% recovery. Statistically-derived
acceptance limits or project defined acceptance limits may be necessary for some
surrogates, including M2PFTeDA, MPFDoA, MPFBA, M2-8:2FTS, M2-6:2FTS, M2-
4:2FTS, d5-N-EtFOSAA, and d3-N-MeFOSAA, as 70-130% default limits may be too
narrow. Consult Method 8000 for information on developing acceptance criteria for
surrogate recovery.
9.7	Initial Calibration Acceptance Criteria (ICAL) - There must be an ICAL of the
LC/MS/MS system as described in Sec. 11. Prior to analyzing samples, verify the ICAL
standards using a second source ICV standard, if readily available (See Sec. 7.4.4.2).
9.8	CCV - The LC/MS/MS system must be verified using the procedure in Sec. 11.
See Method 8000 for the details on carrying out sample QC procedures for preparation
and analysis. In-house method performance criteria for evaluating method performance should
be developed using the guidance found in Method 8000.
9.9	Lower limit of quantitation (LLOQ)
General guidance for LLOQ is provided in this section and in Method 8000. The LLOQ
is the lowest concentration at which the laboratory has demonstrated target analytes can be
reliably measured and reported with a certain degree of confidence. The LLOQ must be greater
than or equal to the lowest point in the calibration curve. The laboratory shall establish the
LLOQ at concentrations where both quantitative and qualitative requirements can consistently
be met (see Sec. 11.6.4). The laboratory shall verify the LLOQ at least annually, and whenever
significant changes are made to the preparation and/or analytical procedure, to demonstrate
quantitation capability at lower analyte concentration levels. The verification is performed by the
extraction and/or analysis of an LCS (or MS) at 0.5 - 2 times the established LLOQ. Additional
LLOQ verifications may be useful on a project-specific basis if a matrix is expected to contain
significant interferences at the LLOQ. The verification may be accomplished with either clean
control material (e.g. reagent water) or a representative sample matrix, free of target
compounds. Optimally, the LLOQ should be less than the desired decision level or regulatory
action level based on the stated DQOs.
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NOTE: LLOQs should be established at concentrations where both quantitative and qualitative
requirements can be consistently and reliably met. Target analyte peaks in the
calibration standard at the LLOQ should be visually inspected to ensure that peak signal
is adequately distinguishable from background and where the signal/noise ratio for all
quantitative peaks is >3. Additional LLOQ verification samples at higher concentrations
may be useful for target analytes with low or no qualifier transitions (e.g., PFBA, PFPeA,
PFHxA) in order to provide better signal to noise and confidence in confirmation.
Additional LLOQ verification samples at higher concentrations may be needed for target
analytes with higher variability, lower response and/or high background (e.g., PFTeDA,
PFTriA, PFDoA, PFUnDA, PF8:2 FTS, 6:2 FTS, N-EtFOSAA, and N-MeFOSAA).
NOTE: If project required levels are sufficiently high, the LCS may be used to meet
requirements of LLOQ verification.
9.9.1 LLOQ Verification
9.9.1.1	The verification of LLOQs using spiked clean control material
represents a best-case scenario because it does not evaluate the potential matrix
effects of real-world samples. For the application of LLOQs on a project-specific
basis, with established DQOs, a representative matrix-specific LLOQ verification
may provide a more reliable estimate of the lower quantitation limit capabilities.
9.9.1.2	The LLOQ verification is prepared by spiking a clean control
material with the analyte(s) of interest at 0.5 - 2 times the LLOQ concentration
level(s). Alternatively, a representative sample matrix free of targets may be
spiked with the analytes of interest at 0.5 - 2 times the LLOQ concentration
levels. The LLOQ check is carried through the same preparation and analytical
procedures as environmental samples and other QC samples.
9.9.1.3	Recovery of target analytes in the LLOQ verification should be
within established in-house limits or within other such project-specific acceptance
limits to demonstrate acceptable method performance at the LLOQ. Preliminary
acceptance criteria for the LLOQ verification are 50-150%. This practice
acknowledges the potential for greater uncertainty at the low end of the
calibration curve. Practical, historically based LLOQ acceptance criteria should
be determined once sufficient data points have been acquired.
9.9.1.4	It is recommended to analyze an LLOQ verification with every
batch of 20 or fewer field samples. In cases where compounds fail low, they may
be reported as non-detects if it can be demonstrated that there was adequate
sensitivity to detect the compound at the LLOQ or project specific level of interest
(e.g., by calibrating below the established LLOQ to confirm the non-detect, or by
analyzing a standard near that level to confirm the analyte could be qualitatively
identified if it were present [See Sec. 11.7 of Method 8000]). Alternatively, the
non-detect could be qualified or the LLOQ raised to a higher level. In cases
where compounds fail high in the LLOQ and are not found in the associated field
samples, they may be reported without qualification.
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9.9.1.5 Reporting concentrations below LLOQ - Concentrations that are
below the established LLOQ may still be reported; however, these analytes must
be qualified as estimated. The procedure for reporting analytes below the LLOQ
should be documented in the laboratory's SOP or in a project-specific plan.
Analytes below the LLOQ that are reported should meet most or all of the
qualitative identification criteria in Sec. 11.6.4.
9.10 It is recommended that the laboratory adopt additional QA practices for use with
this method. Specific practices that are most productive depend upon the needs of the
laboratory, the nature of the samples, and project-specific requirements. Field duplicates may
be analyzed to assess precision of the environmental measurements. Whenever possible, the
laboratory should analyze standard reference materials and participate in relevant performance
evaluation studies.
10.0 CALIBRATION AND STANDARDIZATION
See Sec. 11.0 for information on calibration and standardization.
11.0 PROCEDURE
11.1 Samples are normally prepared by one of the following methods prior to
LC/MS/MS analysis:
Matrix
Methods
Water
Method 3512 (Appendix B)
Soil/sediment
TBD
Biota (fish, plant)
TBD
11.2	Sample cleanup - Cleanup procedures should not be necessary for relatively
clean sample matrices. Extracts from highly contaminated environmental, waste or biota
samples may require additional cleanup steps prior to analysis. The specific cleanup procedure
used will depend upon the analytes of interest, the nature of the interferences, and the DQOs
for the project.
11.3	ICAL
11.3.1 Calibrate the mass spectrometer according to manufacturer's
specifications after any changes to the system and when mass shifts of more than 0.2
Dalton are noticed by the analyst. Acceptable system performance may be
demonstrated by meeting manufacturer specifications for mass resolution, mass
accuracy, and sensitivity using an internal calibrant. Tuning the instrument should only
be performed prior to initial calibration. System calibration must not begin until
manufacturer's performance criteria are met, and calibration standards and samples
must be analyzed under the same conditions.
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NOTE: Prior to running this method and performing the I DP in Sec. 9.4, the laboratory
must optimize instrument settings to obtain acceptable responses for each parent
to product ion transition for every target analyte and surrogate (e.g., cone
voltage, collision energy).
11.3.2	Analyze a consistent volume of each calibration standard (i.e.,
containing the compounds for quantitation and the appropriate surrogates). LC
conditions and MS/MS conditions used in method development are listed in Table 5. A
set of at least five calibration standards must be analyzed with the low standard at or
below the LLOQ (see Sec. 9.9 and Method 8000). Quantitation is based on external
standard calibration models, and a minimum of five standards must be used for average
calibration factor or linear (first-order) calibration models. Six or more standards must be
used for a quadratic (second-order) model. See Sec. 11.4 in Method 8000 for additional
information. The injection volume must be the same for the analysis of all standards and
samples.
NOTE: Concentrations for salt forms of sulfonates are typically corrected to anion
concentration for reporting purposes. For example, in the Wellington standard
(PFAC-24PAR), PFBS salt has a concentration of 2 ug/mL and the anion
concentration is 1.77 ug/mL.
NOTE: LLOQs should be established at concentrations where both quantitative and
qualitative requirements can be consistently and reliably met (see Sees. 9.9 and
11.6). Target analyte peaks in the calibration standard at the LLOQ should be
visually inspected to ensure that peak signal is adequately distinguishable from
background and meets the qualitative requirements outlined in 11.6.
11.3.3	Identify the target compounds using optimized multiple reaction
monitoring (MRM) transitions from Sec. 11.3.1. A qualifier transition is available for most
of the analytes (Table 3).
NOTE: PFAS targets can be calibrated using a summation of the responses for all of the
branched and linear peaks if present in quantitative standards (for example, sum
or integrate all of the C6 sulfonic acid linear and branched isomers as one
calibration point) or by calibrating with only the linear isomer. If a quantitative
standard containing both linear and branched isomers is not available, a
separate technical grade standard may be used to identify retention times of
isomer peaks. Regardless of which calibration procedure is used, quantitation of
targets in samples must include both branched and linear isomers either
summed or integrated together. The data should be reported such that the
calibration choice is clear to the data user. See Figures 1-4, Sec. 17.
11.3.4	Initial calibration calculations
Average calibration factor, linear or quadratic regression models may be used
with this analysis. Calculation of average calibration factors is given below. For linear
and quadratic calculations see Sec. 11.5 in Method 8000.
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11.3.5 Tabulate the response of the quantifier transition (see Table 3 for
suggested ions) against the concentration for each target analyte. Calculate Calibration
factors (CFs) for each target analyte as follows:
peak response of the standard compound
concentration of the compound (ng/L)
11.3.5.1 Calculate the mean CF and the relative standard deviation
(RSD) of the CFs for each target analyte using the following equations:
where:
CFi = CF for each of the calibration standards
~CF = Mean CF for each compound from the ICAL
n = Number of calibration standards (e.g., 5)
SD = Standard deviation
Where n is the number of calibration standards and RSD is expressed as
a percentage (%).
11.3.6	Linearity of target analytes - If the RSD of any target analyte is 20% or
less, then the CF is assumed to be constant over the calibration range, and the average
CF may be used for quantitation (Sec. 11.3.5). The average CF should not be used for
compounds that have an RSD greater than 20%. If a regression model is used for
quantitative purposes, r (correlation coefficient) or r2 (coefficient of determination) should
be > 0.995 or 0.99, respectively. Relative standard error (%RSE) may also be used for
acceptance of the calibration model. See Sec. 11.5.4 of Method 8000 for additional
information. Example RSE calculations can be found in Reference 8. Forcing linear and
quadratic models through the origin may be appropriate when background PFAS are
present to better estimate background concentrations.
11.3.7	When the calibration does not meet the acceptance criteria, the plotting
and visual inspection of a calibration curve can be a useful diagnostic tool. The
inspection may indicate analytical problems, including errors in standard preparation, the
presence of active sites in the chromatographic system, analytes that exhibit poor
chromatographic behavior, etc.
NOTE: It is considered inappropriate once the calibration models have been finalized to
select an alternate fit solely to pass the recommended QC criteria for samples
and associated QC on a case-by-case basis.
mean CF = CF =
n
SD
RSD = = x 100
CF
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11.3.8	If more than 10% of the compounds included with the ICAL (or more
than 10% of those that will be reported) exceed the 20% RSD limit and do not meet the
minimum criteria (r2>0.99 or relative standard error (RSE) <20%) for alternate curve fits,
then the system is considered unacceptable for analysis to begin. Correct the source of
the problem; then repeat the calibration procedure beginning with Sec. 11.3. If
compounds fail to meet these criteria, the associated concentrations may still be
determined but they must be reported as estimated. To report non-detects, it must be
demonstrated that there is sufficient accuracy to detect the failed compounds at the
applicable LLOQ (see Sees. 11.3.9 for refitting standards and 11.4 for CCV).
11.3.9	Calibration, especially when using regression models, has the potential
for a significant bias at the lower portion of the calibration curve. All calibration points
should be recalculated (not reanalyzed) using the final calibration curve in which this
standard is used (i.e., re-fitting the response from the calibration standard back into the
curve and determining % error). See Sec. 11.5.4 of Method 8000 for additional details.
The recalculated concentration of the low calibration point should be within ±50% of the
standard's true concentration, and the recalculated concentrations of any other
calibration standards (above the LLOQ) should be within ±30%. Alternate criteria may
be applied depending on the needs of the project; however, those criteria should be
clearly defined in a laboratory SOP or a project-specific QAPP. Analytes which do not
meet the re-fitting criteria should be evaluated for corrective action (choosing an
alternative model or weighting). If a failure occurs in the low point and it is equivalent to
the LLOQ, the analyte should be reported as estimated near that concentration, or the
LLOQ should be reestablished at a higher concentration.
11.3.10	ICV - Prior to analyzing samples, verify the ICAL using a standard
obtained from a second source to the calibration standard. Suggested acceptance
criteria for the analyte concentrations in this standard are 70 - 130% of the expected
analyte concentration(s). Alternative criteria may be appropriate based on project-
specific DQOs. Quantitative sample analyses should not proceed for those analytes that
do not meet the ICV criteria. However, analyses may continue for those analytes that do
not meet the criteria with an understanding that these results could be used for
screening purposes and would be considered estimated values.
11.4 Continuing Calibration Verification (CCV)
11.4.1	Verify the initial calibration by analyzing a mid-level CCV standard prior
to any samples, after every 10 field samples (or every 12 hours, whichever is shorter),
and at the end of the analytical sequence. The CCV is prepared from the same stock
solutions or source materials used for the ICAL standards. The results must be
compared against the most recent ICAL and should meet the acceptance criteria
provided below.
11.4.2	The calculated concentration or amount of each analyte of interest in
the CCV standard should fall within ±30% of the expected value. If not, a separately
prepared CCV may be prepared and analyzed to meet acceptance criteria.
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11.4.3	If the percent difference (%D) or percent drift for a compound is <30% in
the CCV, then the ICAL for that compound is assumed to be valid. Due to the number of
compounds that may be analyzed by this method, it is expected that some compounds
may fail to meet the criterion. The analyst should strive to place more emphasis on
meeting the CCV criteria for those compounds that are critical to the project. If the
criterion is not met (i.e., greater than ±30%D or drift) for more than 10% of the
compounds included in the ICAL (or more than 10% of those that will be reported), then
corrective action must be taken prior to the analysis of samples. Target analytes that do
not meet the CCV criteria and are reported in the associated samples must be qualified
to indicate the reported concentrations are potentially estimated or biased values. In
cases where compounds fail low, they may be reported as non-detects if it can be
demonstrated that there was adequate sensitivity to detect the compound at the LLOQ
or project specific level of interest (e.g., analysis of an LLOQ verification in every batch,
or by analyzing a standard near that level to confirm the analyte could be qualitatively
identified if it were present [See Sec. 11.7 of Method 8000]). Alternatively, the non-
detect could be qualified or the LLOQ raised to a higher level. In cases where
compounds fail high in the CCV and are not found in the associated field samples, they
may be reported without qualification.
NOTE: For the CF calibration model, %D between the calculated CF of an analyte in the
CCV and the CF of that analyte from the ICAL is the same value as % drift for
calculated versus expected concentration. Refer to Method 8000 for guidance
on calculating %D and % drift.
NOTE: The analyst must closely monitor responses and chromatography in the CCV for
signs that the system is unacceptable for analysis to continue (e.g., unusual
tailing, loss of resolution). If significant losses of target analytes/surrogates occur
(<50% recovery) or if significant degradation of the chromatography occurs,
system maintenance must be performed or the analyst must demonstrate there is
adequate sensitivity at the LLOQ.
11.4.4	A MB or RB must be analyzed after the CCV and prior to samples to
ensure that the system (i.e., introduction device, transfer lines and LC/MS system) is
free from levels of contaminants that would bias the results. If the blank indicates
contamination, then it may be appropriate to analyze additional blanks to help determine
the source of contamination (See Sec. 9.5). A MB or RB is not required after a CCV at
the end of an analytical sequence. Refer to Sec. 9.5.2 regarding qualification of data
and/or corrective actions related to MB or RB contamination.
NOTE: Background of PFAS target analytes may increase in some LC systems while
they are held under initial conditions or while idle; re-started sequences should
typically begin with at least one blank to bleed out any accumulated background
and to provide information about the potential for any carryover in the system.
Refer to Sec. 9.5 for associated acceptance criteria.
11.5 Sample analysis procedure
11.5.1 Inject samples using the same LC and MS/MS conditions as used to
generate the ICAL.
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A suggested sequence order is:
RB
ICAL standards and ICV or opening CCV
MB
LLOQ verification
LCS
Field samples (with a CCV every 10 field samples)
Duplicates
Matrix spike/matrix spike duplicate
Closing CCV
11.5.2	The laboratory should monitor recoveries of the isotopically-labeled
surrogates (listed in Sec. 7.3.11). The percent recovery of each surrogate should fall
within the acceptance criteria, especially for those QC samples prepared in clean
matrices or reagent water (e.g., MB, LCS, LLOQ verification). If multiple surrogates fail
to meet the acceptance criteria and/or the target analytes associated with the failing
surrogate(s) are important to the project, reanalysis and/or repreparation of samples
may be warranted. Otherwise, the associated target analytes may be reported with
appropriate data qualifiers. See additional guidance in Sec. 9.6 of Method 8000.
11.5.3	If the concentration of any analyte exceeds the ICAL range of the
system, the sample extract should be diluted with 50:50 methanol-water with 0.1% acetic
acid and reanalyzed. If dilutions cannot be performed, concentrations that exceed the
calibration range and are reported must be qualified as estimated. When the response of
a compound in the sample exceeds the calibration range, analysis of a RB can help
determine the extent of any carryover that may occur under the conditions used at the
laboratory.
NOTE: The laboratory is cautioned against subsampling of aqueous samples prior to
adding sufficient MeOH, as larger chain PFAS are known to adhere to surfaces
unless the sample contains at least 50% organic cosolvent by volume. See Sec.
8.1.
11.6 Target Identification - MRM analysis provides qualitative identification by isolating
the precursor ion and fragmenting it into the product ions, which are then used to calculate ion
ratios that can be compared between samples and standards to confirm the identification of the
analyte. RTs of target analytes in samples are also compared to those in standards, and RT
shifts of target analytes are compared to associated surrogates in the same samples to further
confirm the identification.
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11.6.1	Identify the target compounds by comparing the quantifier MRM
transitions and applicable qualifier MRM transitions in the sample to the MRM transitions
in the standard. Qualifier transitions are available for most of the analytes (Table 3).
The quantifier/qualifier MRM ion ratio should be within ±30% of the average of the
quantifier/qualifier MRM ion ratios calculated from the calibration levels on the day of
analysis or ±30% of the ion ratios calculated from a mid-level ICAL point or from the
CCV. Some ion ratios may not meet the ±30% criterion at the lower concentrations.
The analyst should use professional judgment when interferences are observed or ion
ratios are not met to prevent reporting false positive or false negative results.
NOTE: Depending on sensitivity and matrix interference issues, a qualifier MRM
transition might be used as a quantifier MRM transition for quantitation during the
analysis. This must be clearly documented if these changes are made.
NOTE: The qualifier ion ratios in samples may not match the ion ratios in the calibration
standards for the target analytes that contain branched and linear isomers.
Figures 1 - 4 (Sec. 17.0) show how branched isomers in samples can be
significantly larger compared to calibration standards for PFHxS and PFOS,
which may cause the ion ratio difference. The complete isomer grouping must be
integrated consistently for all standards and samples.
11.6.2	The RT of the MRM transitions should be within ±10 seconds of the RT
for this analyte in a mid-level ICAL standard, the CCV run at the beginning of the
analytical sequence or the CCV analyzed just prior to the sample (delta RT 0.17 minute).
Alternatively, a relative deviation (in %) may be used for confirmation of target
compounds. The delta RT of the mass labelled analog (surrogate) should also be
considered to confirm target analytes. RT shifts may result in the compound eluting
outside the analytical time segment, which could produce false negative results. Time
segments and RT windows for analytes must include branched chain isomers.
11.7 Analyte quantitation - Once a target compound has been identified, the
quantitation of that compound will be based on the integrated abundance of the quantifier
transition. It is highly recommended to use the integration produced by the software if the
integration is correct because the software should produce more consistent integrations than an
analyst will manually. However, manual integrations may be necessary when the software does
not produce proper integrations because baseline selection is improper; the correct peak is
missed; a co-elution is integrated; the peak is partially integrated; etc. Manual integrations will
be required on most chromatography data systems to include branched and straight chain
isomers where certified individual standards are not available. The analyst is responsible for
ensuring that the integration is correct whether performed by the software or done manually.
Manual integrations should not be substituted for proper maintenance of the instrument or setup
of the method (e.g., RT updates, integration parameter files, etc.). The analyst should seek to
minimize manual integration where practical by properly maintaining the instrument, updating
RTs, and configuring peak integration parameters.
12.0 DATA ANALYSIS AND CALCULATIONS
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12.1 Calculations and documentation - Sample concentrations are quantitated using
the following equations:
Vt = Total volume of extract or diluted sample (in L).
V8 = Volume of aqueous sample prior to preparation (in L).
D = Dilution factor, if sample or extract was diluted prior to analysis. If no
dilution, D=1. This value is always dimensionless.
W8 = Weight of sample extracted (in grams). If kg units are used for this
term, multiply results by 1000 g/kg.
Xs = Calculated concentration of analyte (ng/L) from the analysis. Type of
calibration model used determines derivation ofXs. See Sees. 11.5.1.3,
11.5.2.3, and 11.5.3 of Method 8000.
12.2 See Sees. 11.5 and 11.10 of Method 8000 for additional information and
formulas for quantitating results.
13.0 METHOD PERFORMANCE
Please refer to Tables 2A-2C for a summary of method performance from a multi-
laboratory validation study of aqueous samples prepared by the method in Appendix B (draft
Method 3512).
14.0 POLLUTION PREVENTION
14.1 Pollution prevention encompasses any technique that reduces or eliminates the
quantity and/or toxicity of waste at the point of generation. Numerous opportunities for pollution
prevention exist in laboratory operations. The EPA has established a preferred hierarchy of
environmental management techniques that places pollution prevention as the management
option of first choice. Whenever feasible, laboratory personnel should use pollution prevention
techniques to address their waste generation. When wastes cannot be feasibly reduced at the
source, the Agency recommends recycling as the next best option.
Concentration in
ng _ (XMXD)
L (10
ng
Concentration in —
9
(xs)(v,m
M)
where:
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14.2 For information about pollution prevention that may be applicable to laboratories
and research institutions consult Less is Better: Laboratory Chemical Management for Waste
Reduction, a free publication available from the American Chemical Society (ACS), Committee
on Chemical Safety:
https://www.acs.orq/content/dam/acsorq/about/qovernance/committees/chemicalsafetv/publicati
ons/less-is-better.pdf.
15.0 WASTE MANAGEMENT
The EPA requires that laboratory waste management practices be conducted consistent
with all applicable rules and regulations. The Agency urges laboratories to protect the air,
water, and land by minimizing and controlling all releases from hoods and bench operations,
complying with the letter and spirit of any sewer discharge permits and regulations, and by
complying with all solid and hazardous waste regulations, particularly the hazardous waste
identification rules and land disposal restrictions. For further information on waste
management, consult The Waste Management Manual for Laboratory Personnel available at:
http://www.labsafetvinstitute.org/FreeDocs/WasteMqmt.pdf.
16.0 REFERENCES
1.	ASTM Standard D7979-15, "Standard Test Method for Determination of
Perfluorinated Compounds in Water, Sludge, Influent, Effluent and Wastewater by
Liquid Chromatography Tandem Mass Spectrometry (LC/MS/MS)", 18pp., 2015.
2.	J.A. Shoemaker, P.E. Grimmett, B.K. Boutin, "EPA Method 537- Determination Of
Selected Perfluorinated Alkyl Acids In Drinking Water By Solid Phase Extraction
And Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS) - Research
Summary", U.S. EPA, National Exposure Research Laboratory, Office of Research
and Development, US EPA, Cincinnati, OH, 22pp.
3.	U.S. EPA Method 537.1, "Determination of Selected Per- and Polyfluorinated Alkyl
Substances in Drinking Water by Solid Phase Extraction and Liquid
Chromatography/Tandem Mass Spectrometry (LC/MS/MS)", National Exposure
Research Laboratory, Office of Research and Development, US EPA, Cincinnati,
OH, Version 1.0, 2018.
4.	Occupational Safety and Health Administration, OSHA Safety and Health
Standards, 29 CFR 1910.120, "Hazardous Waste Operations and Emergency
Response" and 29 CFR 1910.1200, "Hazard Communication".
5.	Standard Practices for Sampling Water, American Society for Testing and Materials,
Philadelphia. ASTM Annual Book Standards, Part 31, D3370-76.
6.	R. Burrows, Basic RSE calculator v2 and instructions, December 2016. Available
at: http://nelac-institute.org/docs/comm/emmec/Calculatinq%20RSE.pdf.
7.	Million B. Woudneh, Bharat Chandramouli, M.C. Hamilton, Richard Grace, John R.
Cosgrove, "EFFECT OF SAMPLE STORAGE ON THE QUANTITATIVE
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DETERMINATION OF PFAS - OBSERVATION OF ANALYTE
INTERCONVERSION DURING STORAGE", SETAC 2018, Sacramento, CA, 2018.
17.0 TABLES, DIAGRAMS, FLOWCHARTS, AND VALIDATION DATA
The following pages contain the tables, figures, and appendices referenced by this
method.
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TABLE 1
SUGGESTED LLOQ AND CALIBRATION RANGE
Analyte
Suggested
LLOQ
Calibration Ranges
(ng/L)
PFTeDA
40
10-
400
PFTrDA
40
10-
400
PFDoA
40
10-
400
PFUdA
40
10-
400
PFDA
10
10-
400
PFDS
10
10-
400
PFOS
10
10-
400
PFNA
10
10-
400
PFNS
10
10-
400
PFOA
10
10-
400
PFHpS
40
10-
400
PFHxS
40
10-
400
PFHpA
40
10-
400
PFHxA
40
10-
400
PFBS
10
10-
400
PFPeS
10
10-
400
PFPeA
50
10-
400
PFBA
50
10-
400
FOSA
10
10-
400
4:2 FTS
10
10-
400
6:2 FTS
40
10-
400
8:2 FTS
40
10-
400
N-EtFOSAA
40
10-
400
N-MeFOSAA
40
10-
¦400
NOTE: Calibration ranges listed in this table account for the 2-fold dilution factor of samples with
methanol during preparation, so these LLOQs and the calibration ranges are a factor of two
higher than the calibration standard concentrations provided in Table 4.
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TABLE 2A
LCS PERFORMANCE SUMMARY FROM MULTI-LABORATORY VALIDATION STUDY
Analyte
LCS Recovery (n=48, 160 ng/L, nom.)
LCS/LCSD Relative % Difference (RPD,
n=24 pairs)

Average
recovery
(%)
Standard Deviation
of Recovery
% recovered
within
70-130%
Average
RPD (%)
Standard
Deviation RPD
(%)
# of
LCS/LCSD
pairs with
RPD >30%
P FT re A
103
18.9
89.6
7.1
4.9
100
PFTriA
107
22.7
83.3
8.9
8.0
95.8
PFDoA
104
16.7
91.7
10.3
9.7
95.8
PFUnA
101
12.1
100
9.0
8.7
100
PFDA
102
11.5
97.9
8.9
7.4
95.8
PFNA
103
12.3
95.8
6.9
7.2
100
PFOA
101
12.1
97.9
6.8
6.6
95.8
PFHpA
96.4
8.7
100
5.4
5.3
100
PFHxA
95.8
10.5
100
8.1
7.0
100
PFPeA
94.1
10.1
100
4.1
3.3
100
PFBA
91.5
15.1
87.5
4.4
4.4
100
PFDS
100
10.2
100
5.5
4.8
100
PFNS
105
12.6
100
6.9
6.3
100
PFOS
99.9
8.9
100
5.1
4.9
100
PFHpS
101
9.1
100
5.2
5.2
100
PFHxS
97.9
8.1
100
4.5
4.7
100
PFPeS
98.0
7.2
100
5.5
5.2
100
PFBS
93.2
9.6
100
3.3
5.5
100
PFOSA
98.7
8.2
100
3.6
2.7
100
FtS 8:2
104
15.0
93.8
8.2
6.9
100
FtS 6:2
91.1
33.0
64.6
10.2
8.4
100
FtS 4:2
98.0
12.0
95.8
8.8
8.9
95.8
N-EtFOSAA
102
15.6
93.8
9.0
8.6
95.8
N-MeFOSAA
102
15.2
93.8
9.2
7.7
100
Surroaates:
M2PFTeDA
106
20.4
85.4
9.6
11.8
95.8
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Analyte
LCS Recovery (n=48, 160 ng/L, nom.)
LCS/LCSD Relative % Difference (RPD,
n=24 pairs)

Average
recovery
(%)
Standard Deviation
of Recovery
% recovered
within
70-130%
Average
RPD (%)
Standard
Deviation RPD
(%)
# of
LCS/LCSD
pairs with
RPD >30%
MPFDoA
105
16.6
89.6
11.5
15.5
87.5
M7PFUdA
103
11.3
97.9
8.3
12.2
95.8
M6PFDA
103
13.1
95.8
9.6
14.1
95.8
M9PFNA
102
13.5
97.9
10.0
13.9
91.7
M8PFOA
103
11.9
97.9
9.1
13.1
91.7
M4PFHpA
98.9
12.7
97.9
8.6
13.5
91.7
M5PFHxA
98.7
13.4
97.9
7.3
11.8
95.8
M5PFPeA
97.3
11.6
97.9
5.3
10.4
95.8
MPFBA
95.2
14.7
87.5
5.4
11.8
95.8
M8PFOS
103
13.1
97.9
10.8
12.7
95.8
M3PFHxS
101
12.3
97.9
7.4
11.8
95.8
M3PFBS
95.6
13.5
97.9
7.2
12.2
95.8
M8FOSA-I
103
13.9
95.8
7.1
12.0
95.8
M2-8:2FTS
108
14.4
95.8
8.3
11.3
95.8
M2-6:2FTS
107
17.3
91.7
10.8
11.8
95.8
M2-4:2FTS
103
23.5
87.5
15.7
20.7
87.5
d5-N-EtFOSAA
106
15.3
91.7
11.2
12.9
91.7
d3-N-MeFOSAA
103
13.6
95.8
8.7
10.1
95.8
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TABLE 2B
LLOQ VERIFICATION PERFORMANCE FROM MULTI-LABORATORY VALIDATION
STUDY
Analyte:
10 ng/L (nom., in 5 mL water) LLOQ
verification (n=21)
20 ng/L (nom., in 5 mL water) LLOQ
verification (n=18)

Average
Recovery
(%, non-
zero)
Standard
Deviation of
Recovery
(%, non-
zero)
% within 50-
150%
recovery
Average
recovery
(%, non-
zero)
Standard
Deviation of
Recovery
(%, non-
zero)
% within 50-
150%
recovery
PFTreA
111.6
25.1
81.0
110.2
30.0
94.4
PFTriA
125.6
53.0
71.4
118.2
32.4
83.3
PFDoA
102.9
29.9
81.0
109.3
20.5
94.4
PFUnA
107.6
27.4
81.0
99.9
16.0
100
PFDA
96.8
26.3
85.7
103.1
19.5
94.4
PFNA
100.1
26.1
90.5
99.7
14.1
100
PFOA
100.7
26.8
85.7
99.5
16.3
100
PFHpA
93.2
15.7
100
99.5
13.8
100
PFHxA
99.1
41.6
85.7
94.9
17.6
100
PFPeA
102.7
36.2
85.7
99.1
13.2
100
PFBA
89.1
27.4
85.7
95.2
20.6
94.4
PFDS
104.9
24.6
81.0
100.4
24.2
100
PFNS
102.3
28.5
95.2
105.7
18.0
100
PFOS
111.8
23.0
85.7
106.3
16.8
100
PFHpS
89.1
41.8
90.5
105.1
14.5
100
PFHxS
99.0
17.7
100
99.3
12.7
100
PFPeS
95.8
12.4
100
99.7
12.3
100
PFBS
93.1
17.2
95.2
91.6
12.5
100
PFOSA
100.6
15.0
100
99.7
8.5
100
FtS 8:2
112.4
36.5
66.7
129.0
57.9
72.2
FtS 6:2
1471.4
5540.8
57.1
124.9
152.3
50.0
FtS 4:2
101.6
16.4
90.5
96.2
14.3
100
NEtFOSAA
121.8
33.6
71.4
111.0
18.9
77.8
NMeFOSAA
109.2
52.8
71.4
104.4
34.1
83.3
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TABLE 2C. RECOVERY AND PRECISION OF TARGET ANALYTES AND SURROGATES IN MULTI-LABORATORY STUDY MATRICES
PREPARED BY METHOD 35121
Target Analyte
or Surrogate
name (abbrev)
All matrices (n=479)
Reagent water (n=120)
Groundwater (n=120)
Surface water (n=120)
Wastewater (n=119)
low spike
(60 ng/L nom.)
high spike
(200 ng/L, nom.)
low spike
(60 ng/L nom.)
high spike
(200 ng/L, nom.)
low spike
(60 ng/L nom.)
high spike
(200 ng/L, nom.)
low spike
(60 ng/L nom.)
high spike
(200 ng/L, nom.)
low spike
(60 ng/L nom.)
high spike
(200 ng/L, nom.)
Mean
% Rec.
%
RSD
Mean
% Rec.
% RSD
Mean
% Rec.
%
RSD
Mean
% Rec.
% RSD
Mean
% Rec.
%
RSD
Mean
% Rec.
% RSD
Mean
% Rec.
%
RSD
Mean
% Rec.
% RSD
Mean
% Rec.
%
RSD
Mean
% Rec.
% RSD
PFTreA
89.5
27.3
95.0
18.3
95.5
26.6
101.2
18.5
88.2
24.6
92.9
17.4
83.8
23.4
94.1
16.8
90.7
32.4
91.8
19.3
PFTriA
95.7
25.2
99.8
18.2
97.7
22.8
102.5
17.6
95.8
25.4
99.3
17.6
92.3
24.7
99.4
17.8
97.2
28.2
98.2
20.4
PFDoA
95.8
25.2
102.1
18.0
95.8
24.3
103.0
14.5
98.0
26.2
102.8
19.5
93.9
20.9
101.2
19.0
95.6
29.3
101.2
19.2
PFUnA
97.3
18.9
104.2
16.1
98.9
18.6
104.5
15.2
96.0
17.4
103.3
16.8
96.3
20.1
103.0
13.2
98.2
19.7
106.0
18.7
PFDA
99.4
18.8
104.4
12.7
102.1
19.9
105.5
14.8
98.2
20.3
102.0
10.7
97.2
17.1
103.5
12.1
100.0
18.0
106.4
12.7
PFNA
96.8
14.3
102.1
11.4
97.0
12.5
103.5
11.1
96.5
16.2
100.6
10.5
95.1
15.4
100.9
12.8
98.5
13.0
103.3
11.4
PFOA
99.9
13.9
103.2
10.6
100.0
13.8
104.4
10.8
98.8
13.9
102.0
11.3
100.6
15.8
102.6
9.7
100.2
12.5
103.8
10.7
PFHpA
97.9
13.3
100.0
9.2
98.5
13.0
101.3
9.8
96.2
13.3
98.8
8.5
95.6
15.7
100.0
8.1
101.3
10.5
100.1
10.4
PFHxA
97.2
18.4
98.5
11.2
97.4
13.5
99.5
11.0
95.0
14.8
96.9
10.5
98.2
22.3
98.9
9.9
98.2
21.7
98.7
13.5
PFPeA
106.5
24.7
100.3
12.6
104.0
17.2
100.1
13.1
112.7
38.4
100.2
11.7
102.5
17.8
99.5
11.8
107.0
14.1
101.5
14.0
PFBA
93.6
24.1
94.8
17.5
93.1
23.6
96.4
18.6
98.0
22.5
97.2
12.0
86.7
29.0
90.2
19.4
96.6
20.5
95.4
18.9
PFDS
95.7
20.4
100.3
17.6
97.7
18.1
103.5
15.2
95.6
20.2
102.2
16.0
94.4
22.1
100.1
16.0
95.1
21.7
95.5
22.5
PFNS
100.4
17.8
105.6
13.9
101.7
16.5
106.1
14.0
99.8
18.6
106.1
13.7
99.4
19.5
105.6
12.7
100.6
17.2
104.4
15.6
PFOS
103.5
17.8
108.0
27.9
100.0
19.5
104.1
11.4
102.5
17.9
105.1
11.5
103.5
15.6
103.3
10.3
108.1
18.0
119.5
46.7
PFHpS
98.9
14.2
102.4
10.2
101.2
13.6
103.9
10.1
97.5
15.2
101.6
9.4
96.5
14.5
100.2
10.5
100.2
13.4
103.9
10.8
PFHxS
97.2
15.9
102.1
10.5
95.3
16.4
101.1
9.9
94.9
18.7
100.5
7.6
96.9
14.0
101.3
8.1
101.7
14.1
105.6
14.3
PFPeS
96.0
10.8
99.3
00
00
96.8
9.8
99.0
9.1
95.8
10.2
99.2
8.2
95.3
14.0
98.7
8.9
96.3
8.6
100.1
9.1
PFBS
96.7
14.4
99.8
11.1
92.7
12.1
100.0
12.3
99.1
15.9
100.5
9.9
94.9
15.1
99.2
10.9
100.0
13.0
99.5
11.7
PFOSA
88.7
14.1
95.5
10.6
87.7
12.4
92.1
11.1
89.6
13.9
97.3
10.4
85.2
18.3
94.2
7.9
92.4
10.3
98.6
11.4
FtS82
102.6
20.1
109.7
16.1
105.1
13.9
108.8
13.4
100.9
20.8
105.1
12.9
93.9
20.0
106.7
15.3
110.6
21.8
118.2
18.9
FtS62
95.0
192
92.4
51.8
85.5
49.7
92.3
29.3
75.6
34.1
97.1
84.4
130.3
275.5
86.2
33.8
88.4
37.0
93.9
33.5
FtS42
95.1
19.7
102.1
14.4
98.5
15.9
104.0
9.5
91.0
21.5
97.6
12.5
92.2
18.6
101.1
14.2
98.7
21.7
105.7
18.8
8327- 34
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Target Analyte
or Surrogate
name (abbrev)
All matrices (n=479)
Reagent water (n=120)
Groundwater (n=120)
Surface water (n=120)
Wastewater (n=119)
low spike
(60 ng/L nom.)
high spike
(200 ng/L, nom.)
low spike
(60 ng/L nom.)
high spike
(200 ng/L, nom.)
low spike
(60 ng/L nom.)
high spike
(200 ng/L, nom.)
low spike
(60 ng/L nom.)
high spike
(200 ng/L, nom.)
low spike
(60 ng/L nom.)
high spike
(200 ng/L, nom.)
Mean
% Rec.
%
RSD
Mean
% Rec.
% RSD
Mean
% Rec.
%
RSD
Mean
% Rec.
% RSD
Mean
% Rec.
%
RSD
Mean
% Rec.
% RSD
Mean
% Rec.
%
RSD
Mean
% Rec.
% RSD
Mean
% Rec.
%
RSD
Mean
% Rec.
% RSD
NEtFOSAA
99.3
26.4
106.6
20.1
96.5
24.1
104.0
21.6
97.6
29.2
107.7
21.3
99.0
26.3
105.4
18.7
104.4
26.2
109.4
19.1
NMeFOSAA
98.2
22.7
101.7
16.6
98.6
18.4
100.4
13.6
96.0
20.1
103.3
17.2
98.5
28.9
103.0
18.0
99.8
22.5
100.0
17.7
M2PFTeDA
95.2
21.3
99.8
18.2
99.9
22.2
100.8
18.1
91.6
20.1
97.0
17.3
93.2
21.4
98.5
14.9
96.0
21.1
102.9
21.7
MPFDoA
100.3
15.1
101.2
15.1
100.4
14.0
101.9
8.9
98.1
12.9
98.7
14.2
99.6
17.5
98.6
13.0
103.2
15.6
105.6
20.8
M7PFUdA
103.0
11.8
104.3
12.6
102.8
11.2
104.3
10.0
101.9
13.3
101.9
11.3
101.8
11.6
103.1
10.4
105.6
11.3
107.8
16.8
M6PFDA
104.5
11.7
105.0
13.2
103.1
9.8
105.6
9.5
103.8
12.9
104.8
9.4
105.2
12.5
102.3
11.0
105.8
11.6
107.3
19.6
M9PFNA
101.9
12.0
101.8
13.0
102.0
11.4
102.7
10.3
101.1
14.7
100.6
11.6
103.5
11.4
101.1
11.5
101.1
10.4
102.8
17.6
M8PFOA
100.6
10.5
101.2
11.5
100.9
10.6
101.2
7.8
99.4
11.5
99.6
9.6
101.6
10.9
101.0
8.2
100.4
9.0
102.9
17.4
M4PFHpA
98.5
12.0
98.8
12.8
99.8
10.7
99.6
8.7
99.0
13.1
97.1
8.1
98.8
11.0
98.8
8.6
96.2
13.3
99.9
21.1
M5PFHxA
96.6
12.8
97.7
13.6
98.2
11.5
99.0
10.1
96.4
13.5
97.9
10.7
96.3
14.4
96.7
11.2
95.4
12.0
97.4
20.3
M5PFPeA
98.3
7.8
99.0
11.2
97.9
8.2
99.3
7.9
96.9
8.2
99.3
6.1
99.2
7.6
97.2
7.2
99.2
7.2
100.4
18.5
MPFBA
95.1
12.6
96.5
12.2
93.0
15.0
95.9
11.4
97.3
9.6
97.0
7.1
94.1
12.9
94.2
10.2
96.1
12.4
98.9
17.4
M8PFOS
98.9
11.5
100.2
13.1
97.8
9.1
99.6
9.9
100.3
9.5
100.5
9.4
98.9
13.1
98.8
9.7
98.7
13.7
101.8
20.0
M3PFHxS
95.4
7.8
96.2
11.0
94.4
7.4
96.6
5.9
95.6
8.7
94.8
6.6
95.7
8.3
95.1
8.9
95.8
6.9
98.3
17.9
M3PFBS
89.8
12.3
89.9
15.7
89.4
10.6
91.0
10.3
90.2
11.2
91.2
9.2
90.1
13.7
86.7
19.2
89.5
13.7
90.8
20.9
M8FOSAI
108.3
9.1
108.7
12.3
108.6
7.6
107.5
7.2
107.3
9.1
108.6
8.7
108.5
10.0
107.8
12.3
108.8
9.6
110.8
18.0
M282FTS
106.8
12.7
114.0
15.0
104.4
14.1
112.3
11.8
104.8
14.0
110.3
11.7
107.8
12.6
111.4
12.9
110.3
9.3
122.0
19.3
M262FTS
99.1
18.5
105.1
15.2
98.0
13.7
105.8
11.2
95.2
10.9
100.6
10.6
104.4
29.2
103.9
14.1
98.9
10.0
110.0
20.9
M242FTS
93.4
19.2
99.3
22.4
97.0
18.2
98.7
16.5
87.6
22.8
94.9
20.6
93.3
13.9
100.3
27.0
95.9
20.4
103.3
23.8
d5NEtFOSAA
110.8
14.9
109.3
16.3
107.6
13.3
107.9
14.2
108.0
13.1
106.1
16.7
112.7
16.5
109.0
15.9
115.2
15.7
114.2
17.7
d3NMeFOSAA
107.8
15.7
106.2
17.5
106.4
13.4
103.9
13.5
105.2
14.4
108.2
17.7
110.8
19.5
105.2
14.6
108.9
14.6
107.4
22.8
1% Recovery of each replicate sample was calculated after subtracting average unspiked concentration by matrix determined at each laboratory if the average unspiked
concentration was > 5 ng/L.
8327- 35
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TABLE 3
RETENTION TIME (RT) AND MRM IONS
Chemical
Quantifier/Qualifier MRM Transition
RT
(minutes)
PFTeDA
Quantifier
Qualifier
713—>669
713—>169
10.6
PFTrDA
Quantifier
Qualifier
663—>619
663—>169
10.2
PFDoA
Quantifier
Qualifier
613—>569
613—>169
9.6
PFUdA
Quantifier
Qualifier
563—>519
563—>269
9.0
PFDA
Quantifier
Qualifier
513—>469
513—>219
8.4
PFDS
Quantifier
Qualifier
599—>80
599—>99
9.8
PFOS
Quantifier
Qualifier
499—>80
499—>99
8.8
PFNA
Quantifier
Qualifier
463—>419
463—>219
7.8
PFNS
Quantifier
Qualifier
549—>80
549—>99
9.2
PFOA
Quantifier
Qualifier
413—>369
413—>169
7.1
PFHpS
Quantifier
Qualifier
449—>80
449—>99
7.9
PFHxS
Quantifier
Qualifier
399—>80
399—>99
7.4
PFHpA
Quantifier
Qualifier
363—>319
363—>169
6.3
PFHxA
Quantifier
Qualifier
313—>269
313—*-119
5.5
8327- 36
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Chemical Quantifier/Qualifier MRM Transition
(minutes)
Quantifier	299—>80
PFBS 	 5.7
Qualifier	299—>99
PFPeA	Quantifier	263—>219	4.7
Quantifier	349—>80
PFPeS 	 6.4
Qualifier	349—>99
PFBA	Quantifier	213^169	3.7
Quantifier	327—>307
4:2 FTS 	 5.2
Qualifier	327—>81
Quantifier	427—>407
6:2 FTS 	 6.7
Qualifier	427—>81
Quantifier	527—>507
8:2 FTS 	 8
Qualifier	527—>81
Quantifier	570—>419
N-MeFOSAA 	 8.4
Qualifier	570—>483
Quantifier	584—>419
N-EtFOSAA 	 8.7
Qualifier	584—>483
FOSA	Quantifier	498—>78	9.8
M4PFBA	Quantifier	217^172	3.7
M5PFHxA	Quantifier	318^273	5.5
M3PFHxS	Quantifier	402^80	7.4
M8PFOA	Quantifier	421^376	7.1
M9PFNA	Quantifier	472^427	7.8
M8PFOS	Quantifier	507—>80	8.8
M6PFDA	Quantifier	519^474	8.4
M7PFUdA	Quantifier	570^525	9.0
M2PFDoA	Quantifier	615—>570	9.6
M2-4:2 FTS	Quantifier	329^309	5.2
M2-6:2 FTS	Quantifier	429^409	6.7
M2-8:2 FTS	Quantifier	529^509	8.0
d3-N-MeFOSAA	Quantifier	573^419	8.4
d5-N-EtFOSAA	Quantifier	589^419	8.7
8327- 37
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Chemical
Quantifier/Qualifier
MRM Transition
RT
(minutes)
M3PFBS
Quantifier
302—>80
5.7
M5PFPeA
Quantifier
268—>223
4.7
M4PFHpA
Quantifier
367—>322
6.3
M2PFTeDA
Quantifier
715—>670
10.6
M8FOSA
Quantifier
506—>78
9.8
Note: Acceptable qualifier ions were not identified for PFBA and PFPeA during method
development; qualifier ions are not identified for the surrogates
TABLE 4
PREPARATION OF CALIBRATION STANDARDS*
ICAL 5 ng/L 10ng/L 20 ng/L 40 ng/L 60 ng/L 80 ng/L 100ng/L 150ng/L 200 ng/L
Levels
PDS 25 (jL 50 (jL 100 |jL 200 |jL 300 |jL 400 |jL 500 |jL 750 |jL 1000 |jL
Solution 975 |jL 950 |jL 900 |jL 800 |jL 700 |jL 600 |jL 500 |jL 250 |jL 0 |jL
B
PDS: 200 ng/L stock solution prepared according to Section 7.4.4
Solvent: 50:50 methanol-water with 0.1% acetic acid.
* These values are the nominal concentrations in the calibration standards. The
concentration obtained from the instrument is then corrected for the 2-fold dilution made during
the sample preparation process producing the reporting ranges in Table 1. Salt concentrations
may also require conversion to the anion for reporting purposes. For example in the Wellington
standard (PFAC-24PAR), PFBS salt has a concentration of 2 ug/mL and the anion is 1.77
ug/mL.
8327- 38
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TABLE 5A
EXAMPLE OF TERNARY GRADIENT CONDITIONS FOR LIQUID
CHROMATOGRAPHY
To prepare 1 liter of solvent C, dissolve 30.8 g of ammonium acetate in 950 mL of
reagent water and add 50 mL of acetonitrile.
Time (min)
Flow
(mL/min)
% Solvent Line A
95% water:
5% acetonitrile
% Solvent Line B
Acetonitrile
% Solvent Line C
400mM ammonium acetate
(95% water: 5% acetonitrile)
0
0.3
95
0
5
1
0.3
75
20
5
6
0.3
50
45
5
13
0.3
15
80
5
14
0.4
0
95
5
17
0.4
0
95
5
18
0.4
95
0
5
21
0.4
95
0
5
8327- 39
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TABLE 5B
EXAMPLE OF BINARY GRADIENT CONDITIONS FOR LIQUID CHROMATOGRAPHY
To prepare 1 liter of solvent A, dissolve 1.54 g of ammonium acetate in 950 mL of
reagent water and add 50 mL of acetonitrile.
To prepare 1 liter of solvent B, dissolve 0.771 g of ammonium acetate in 50 mL of
reagent water and add 950 mL of acetonitrile


% Solvent Line A
% Solvent Line B
Time
(min)
Flow
(mL/
min)
20mM ammonium
acetate in 95% water:
5% acetonitrile
10mM* ammonium
acetate in 95%
acetonitrile: 5%
water
0
0.3
100
0
1
0.3
80
20
6
0.3
50
50
13
0.3
15
85
14
0.4
0
100
17
0.4
0
100
18
0.4
100
0
21
0.4
100
0
20 mM ammonium acetate may not be solub
e in 95:5 acetonitrile-water
8327- 40
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TABLE 5C
INSTRUMENT CONDITIONS USED IN METHOD DEVELOPMENT
Analytical column: See 6.1.2
Isolator Column: See 6.1.3
Column temperature: 35-50°C.
Injection volume: 10-30|jL
Needle wash: 60% acetonitrile / 40% 2-propanol
Instrument: Waters Xevo TQ-S
Capillary voltage: 0.75 kV
Source temperature: 150°C
Desolvation gas temperature: 450°C
Desolvation gas flow: 800 L/hr
Cone gas flow: 200 L/hr
Collision gas flow: 0.15 mL/min
8327- 41
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TABLE 6
EXAMPLES OF SURROGATES AND RECOMMENDED TARGET ANALYTE
ASSOCIATIONS
Examples of Isotooicallv Labeled PFAS Surroaates
Recommended taraet analvte association(s)
Sulfonic Acid Surroaates

Perfluoro-1-[2,3,4-13C3]butanesulfonic acid (M3PFBS)
PFBS,PFPeS
Perfluoro-1 -[1,2,3-13C3]hexanesulfonic acid (M3PFHxS)
PFHxS, PFHpS
Perfluoro-1-[13C8]octanesulfonic acid (M8PFOS)
PFOS, PFNS, PFDS
1H, 1H, 2H, 2H-perfluoro-1-[1,2-13C2] hexanesulfonic
acid (M2-4:2 FTS)
4:2FTS
1H, 1H, 2H, 2H-perfluoro-1-[1,2-13C2] octanesulfonic
acid (M2-6:2 FTS)
6:2FTS
1H, 1H, 2H, 2H-perfluoro-1-[1,2-13C2] decanesulfonic
acid (M2-8:2 FTS)
8:2FTS
Carboxvlic Acid Surroaates

Perfluoro-n-[13C4]butanoic acid (M4PFBA)
PFBA
Perfluoro-n-[13C5]pentanoic acid (M5PFPeA)
PFPeA
Perfluoro-n-[1,2,3,4,6-13C5]hexanoic acid (M5PFHxA)
PFHxA
Perfluoro-n-[1,2,3,4-13C4]heptanoic acid (M4PFHpA)
PFHpA
Perfluoro-n-[13C8]octanoic acid (M8PFOA)
PFOA
Perfluoro-n-[13C9]nonanoic acid (M9PFNA)
PFNA
Perfluoro-n-[1,2,3,4,5,6-13C6]decanoic acid (M6PFDA)
PFDA
Perfluoro-n-[1,2,3,4,5,6,7-13C7]undecanoic acid
(M7PFUdA)
PFUdA
Perfluoro-n-[1,2-13C2]dodecanoic acid (M2PFDoA)
PFDoA, PFTrDA
Perfluoro-n-[1,2-13C2]tetradecanoic acid (M2PFTeDA)
PFTeDA
Sulfonamide and Sulfonamidoacetic acid Surroaates:

Perfluoro-1 -[13C8]octanesulfonamide (M8FOSA)
PFOSA
N-methyl-d3-perfluoro-1 -octanesulfonamidoacetic acid
(d3-N-MeFOSAA)
N-MeFOSAA
N-ethyl-d5-perfluoro-1 -octanesulfonamidoacetic acid
(d5-N-EtFOSAA)
N-EtFOSAA
8327- 42
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TABLE 7
QC SUMMARY
Quality control type
Specification and
minimum frequency
Acceptance criteria
Initial demonstration of proficiency
(IDP) (Sec. 9.4)
4 replicates at mid
calibration level initially and
after major changes
Meet %recovery / %RSD
requirements
Sample holding time
(Sec. 8.2)
Samples: 28 days
Extracts: 30 days
TBD (pending holding time study)
Initial Calibration (ICAL)
(Sec. 9.7, 11.3)
Prior to analysis of samples
Mean CF: (%RSD<20)
linear or quadratic regression: r2 >0.99
%Error: <±50% at LLOQ and <±30%
for all others
>90% of targets and surrogates meet
ICAL criteria
Initial calibration verification
(ICV)(Sec. 9.7, 11.3.10)
After initial calibration and
prior to analysis of samples
Target analytes are within ±30% of
expected concentrations
Continuing calibration verification
(CCV)
(Sec. 9.8, 11.4)
At beginning, every 10
samples and at end
>90% of target analytes and
surrogates within ±30% of expected
concentrations
Reagent Blank (RB)
(Sec. 9.5.7)
One per day of analysis
Target analyte concentrations <1/2
LLOQ or <10% of sample
concentrations
Method Blank (MB)
(Sec. 9.5, 11.4.4)
One per preparation of 20 or
fewer samples
Target analytes <1/2 LLOQ or <10% of
sample concentration
LLOQ verification
Sec. 9.9.1
One per preparation batch
of 20 or fewer samples
Target analytes 50-150% recovery
Laboratory Control Sample (LCS)
Sec. 9.6.2
One per preparation batch
of 20 or fewer samples
Target analytes 70-130% recovery
Surrogates
Sec. 9.10
Each sample
Surrogates 70-130% recovery;
Target analytes
Section 11.6

Meets qualitative ID criteria (RT in
sample is within ±10 sec. of CCV, or
RT shift is similar to associated
surrogate; qualifier ion ratio within
±30% of expected ratio (midpoint ICAL
or CCV), as applicable
Matrix spike/duplicate or matrix
spike/matrix spike duplicate
(MS/MSD)
(Sec. 9.6.1)
One set per preparation of
20 or fewer field samples (if
sufficient replicate samples
are provided)
MS/MSD targets: 70-130% recovery
MSD or duplicate: <30% RPD
8327- 43
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FIGURE 1
PFOS IN CALIBRATION STANDARD
82316lev4 Smooth(Mn,1x2)
100-
PFOS79.7 ;8.59:8331.389:133723
PFOS79.7
8.59
8331.389
133723
F14:MRM of 3 channels,ES-
498.9 >79.9
1,344e+005
u 	
82316lev4 Smooth(Mn,1x2)
100-1
T
t
T
T
1 min
PFOS79.7 ;8.59:5853.411 ;101547
PFOS79.7
8.59
5853.411
101547
F14:MRM of 3 channels,ES-
498.9 >98.9
1,020e+005
I 1 1 1 1 I 1 1 1 1 I
8.800
8.100
8.200
8.300
8.400
8.500
8.600
8.700
FIGURE 2
PFOS IN GROUNDWATER SAMPLE
Note: The peak at 8.22 min is an example of a structural isomer of PFOS evident in a
sample that was not observed in the calibration standard for used for quantitation.
8231608004_16 Smooth(Mn,1x2)
1608004_16RE1
100-
PFOS79.7:8.39:19437.021 ;155029
8231608004_16 Smooth(Mn,1x2)
1608004_16RE1
100-1
PFOS79.7;8.59;10192.644:97328
PFOS79.7
8.59
PFOS79.7
8.59
10192.644 10192.644
8.22
F14:MRM of 3 channels,ES-
498.9 >79.9
1,559e+005
1943/.021
155029
mm
F14:MRM of 3 channels,ES-
498.9 >98.9
9.733e+004
8.100
8.200
8.300
8.400
8.500
8.600
8.700
8.800
8327- 44
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FIGURE 3
PFHxS IN CALIBRATION STANDARD
82316lev4 Sm ooth(Mn,1x2]
100-
PFHxS80.1;7.22;9600.141;160784
PFHXS80 1
PFH >580 1
9600141
9600 1 41
'bU?o4
"HU7b4
1 I 1 ¦¦ ¦i ¦ ¦ ¦ 			I | | iii . i .. i i i i i |i .i i | i i i i | i ii i | i
F8:MRM of6 channels.ES-
398.9 > 79.9
1 617e+005
	
82316 ev4 Sm ooth (Mn,1x2)
100-
PFHXS80-1:7.22:7502.227:133539
PFHX380.1
7.22
7502.227
133539
F8:MRM of6 channels.ES-
398.9 >98.9
1 335e+005
	
6.90	7.00	7.10	7.20	7.30	7.40	7.50	7.60	7.70
6.80
FIGURE 4
PFHxS IN GROUNDWATER SAMPLE
8231608004_21 Smooth (Mn,1x2)
160 8004_21 RE 1
100n
PFHxS 80.1:7.22:277470.1882631085
PrHXS80.1
7.22
277470.188
2631085
F8:MRM of 6 channels.ES-
398.9 > 79.9
2.636e+006
'I 1 1 1 1 I 1 1 1 1 I 11 1 1 I 1 1 1 1 I 1 111 I 1 1 1 1 I 111 1 I 1 1 1 1 I 1 1 11 I 1 1 1 1 I 1 1 1 1 I 1 11 1 I 1 1 1 1 I 1 1 1 1 I 1 1 1 1 I 1 11 1 I 1 1 1 1 I 1 11 1 I 1 1 1 1 I
8231608004_21 Smooth (Mn.1x2)
1608004_21RE1
100-,
PFH xS80.1:7.22:377356:906:4666832
PFHXS80.1
7.22
377356.906
4666832
F8:MRM of6 channels.ES-
398.9 > 98 .9
4.685e+006
1 I 1 11 1 I 1 1 1 1 I 11 1 1 I 1 1 1 1 I 1 111 I 1 1 1 1 I 111 1 I ' 1 1 ' I 1 1 11 I 1 1 1 ' I ' '' 1 I 1 1,1 I ' 1 11 I 1 11 1 I 11 11 I 1 1 1 1 I 1 1 11 I 1 11 1 I 1 1 11 I ''
6.80	6.90	7.00	7.10	7.20	7.30	7.40	7.50	7.60	7.70
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APPENDIX A - GLOSSARY
ASTM
ASTM International, formerly American Society for Testing and Materials
CAS RN
Chemical Abstract Service Registry Number®
CCV
continuing calibration verification
DQOs
Data Quality Objectives
EPA
U.S. Environmental Protection Agency
HDPE
high density polyethylene
ICAL
initial calibration
ICV
initial calibration verification
IDP
initial demonstration of proficiency
LC
liquid chromatography
LC/MS/MS
liquid chromatography/tandem mass spectrometry
LCS
laboratory control sample
LCSD
laboratory control sample duplicate
LLOQ
lower limit of quantitation
MB
method blank
MeOH
methanol
MRM
multiple reaction monitoring
MS
mass spectrometer
MS/MSD
matrix spike / matrix spike duplicate
OSHA
U.S. Occupational Safety and Health Administration
PEEK
Polyetheretherketone
PFAS
per- and polyfluoroalkyl substances
PPE
personal protective equipment
P&B
precision and bias
PTFE
polytetrafluoroethylene
QA
quality assurance
QAPP
quality assurance project plan
QC
quality control
RB
reagent blank
RSD
relative standard deviation
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RT
retention time
Delta RT
delta retention time (in minutes or seconds)
SAP
sampling and analysis plan
SDS
safety data sheet
SOP
standard operating procedure
SRM
single reaction monitoring
TBD
to be determined
UPLC
ultraperformance liquid chromatograph
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APPENDIX B (future Method 3512) - AQUEOUS SAMPLE PREPARATION
Note: The aqueous sample preparation procedure in this appendix will become a new
standalone preparation method (Method 3512) after the validation study is complete and the
public comments for the analytical method have been addressed. This follows the typical
modular approach for SW-846 methods allowing this preparation procedure to be combined with
other analytical methods, once available.
METHOD 3512
PER AND POLYFLUORINATED ALKYL SUBSTANCES (PFAS^ IN NON-POTABLE WATER
BY SOLVENT DILUTION
SW-846 is not intended to be an analytical training manual. Therefore, method
procedures are written based on the assumption that they will be performed by analysts who are
formally trained in at least the basic principles of chemical analysis and in the use of the subject
technology.
In addition, SW-846 methods, with the exception of required method use for the analysis
of method-defined parameters, are intended to be guidance methods which contain general
information on how to perform an analytical procedure or technique which a laboratory can use as
a basic starting point for generating its own detailed standard operating procedure (SOP), either
for its own general use or for a specific project application. The performance data included in this
method are for guidance purposes only and are not intended to be and must not be used as
absolute QC acceptance criteria or for the purpose of laboratory accreditation.
B1.0 SCOPE AND APPLICATION
B1.1 Method 3512 is a preparation procedure for diluting non-potable water samples
with an organic solvent prior to analysis by the appropriate determinative method for PFAS. This
microscale approach minimizes sample size and solvent usage, thereby reducing the supply
costs, health and safety risks, and waste generated.
B1.2 The 24 PFAS that have been evaluated with this preparation method are
provided below. This preparation method was validated in conjunction with determinative
Method 8327 and included mass-labelled analogs as surrogates. See Method 8327 for
performance data. These surrogates may also be used as isotope dilution internal standards
using Method 8328. This method has been tested in reagent water, surface water,
groundwater, and wastewater matrices.
Analvte	CAS RN*
PFAS sulfonic acids
Perfluoro-1-butanesulfonic acid (PFBS)	375-73-5
Perfluoro-1-pentanesulfonic acid (PFPeS)	2706-91-4
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Analvte
CAS RN*
Perfluoro-1-hexanesulfonic acid (PFHxS)
355-46-4
Perfluoro-1-heptanesulfonic acid (PFHpS)
375-92-8
Perfluoro-1-octanesulfonic acid (PFOS)
1763-23-1
Perfluoro-1-nonanesulfonic acid (PFNS)
68259-12-1
Perfluoro-1-decanesulfonic acid (PFDS)
335-77-3
1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS)
757124-72-4
1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS)
27619-97-2
1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS)
39108-34-4
PFAS carboxvlic acids

Perfluorobutanoic acid (PFBA)
375-22-4
Perfluoropentanoic acid (PFPeA)
2706-90-3
Perfluorohexanoic acid (PFHxA)
307-24-4
Perfluoroheptanoic acid (PFHpA)
375-85-9
Perfluorooctanoic acid (PFOA)
335-67-1
Perfluorononanoic acid (PFNA)
375-95-1
Perfluorodecanoic acid (PFDA)
335-76-2
Perfluoroundecanoic acid (PFUdA)
2058-94-8
Perfluorododecanoic acid (PFDoA)
307-55-1
Perfluorotridecanoic acid (PFTrDA)
72629-94-8
Perfluorotetradecanoic acid (PFTeDA)
376-06-7
PFAS sulfonamides and sulfonamidoacetic acids

N-ethylperfluoro-1-octanesulfonamidoacetic acid (N-
2991-50-6
EtFOSAA)

N-methylperfluoro-1-octanesulfonamidoacetic acid (N-
2355-31-9
MeFOSAA)

Perfluoro-1-octanesulfonamide (FOSA)
754-91-6
*Standards for some target analytes may consist of mixtures of structural
isomers; however, the Chemical Abstracts Service (CAS) Registry Number (RN) listed in
the table is for the normal-chain isomer. All CAS RNs in the above table are for the acid
form. Sulfonic acids in stock standard mixes are typically received as the sodium or
potassium salt form. CAS RNs for the salt form are not included.
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B1.3 This technique may also be applicable to other PFAS compounds, provided that
the analyst demonstrates adequate performance (e.g., recovery of 70 - 130%, or at levels that
meet project-specific recovery criteria) using spiked sample matrices and an appropriate
determinative method of the type included as an 8000 series method in SW-846. The use of
organic-free reagent water alone is not considered sufficient for conducting such performance
studies; performance must be supported by data from actual sample matrices.
B1.4 This method may not be appropriate for aqueous samples with high levels of
suspended solids. If significant particulate matter is present and the total sample is of concern,
then the sample should be treated as a multi-phase sample per SW-846 Chapter Two.
B1.5 Prior to employing this method, analysts are advised to consult the base method
for each type of procedure that may be employed in the overall analysis (e.g., Methods 3500,
3600, and 8000) for additional information on quality control procedures, development of QC
acceptance criteria, calculations, and general guidance. Analysts also should consult the
disclaimer statement at the front of the manual and the information in SW-846 Chapter Two for
guidance on the intended flexibility in the choice of methods, apparatus, materials, reagents,
andsupplies, and on the responsibilities of the analyst for demonstrating that the techniques
employed are appropriate for the analytes of interest, in the matrix of interest, and at the levels
ofconcern.
In addition, analysts and data users are advised that, except where explicitly required in
a regulation, the use of SW-846 methods is not mandatory in response to Federal testing
requirements. The information contained in this method is provided by EPA as guidance to be
used by the analyst and the regulated community in making judgments necessary to generate
results that meet the data quality objectives for the intended application.
B1.6 Use of this method is restricted to use by, or under supervision of, appropriately
experienced and trained personnel. Each analyst must demonstrate the ability to generate
acceptable results with this method.
B2.0 SUMMARY OF METHOD
B2.1 Samples are prepared by adding mass-labelled PFAS isotopes (as surrogates or
as isotope dilution internal standards, depending on determinative method), diluting samples 1:1
with the appropriate organic solvent, filtering and pH adjustment, if necessary.
B2.2 Determinative analysis is performed using the appropriate LC/MS/MS method
(e.g., 8327, 8328).
B3.0 DEFINITIONS
Refer to the SW-846 Chapter One for and the manufacturer's instructions for definitions
that may be relevant to this procedure.
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B4.0 INTERFERENCES
B4.1 In order to avoid compromising data quality, contamination from preparation
procedure must be reduced to the lowest practical level. Method blanks (MBs) and reagent
blanks (RBs) are prepared and analyzed with all samples and are used to demonstrate that
laboratory supplies and preparation and analysis steps do not introduce interferences or PFAS
artifacts at levels that would bias quantitation. Careful selection of reagents and consumables is
necessary because even low levels of PFAS contamination may alter the precision and bias of
the method, and background introduced by these materials (and variability thereof) is
cumulative. Refer to each determinative method to be used for specific guidance on QC
procedures and to SW-846 Chapter Four for general guidance on glassware cleaning.
B4.2 Refer to Method 8327 or 8328 for additional information on interferences.
B4.3 Procedures employed to prevent or minimize problems.
B4.3.1 All solvents should be of pesticide residue purity or higher (or
preferably LC/MS grade) to minimize interference problems.
B4.3.2 PFAS contamination has been found in reagents, glassware, tubing,
polytetrafluoroethylene (PTFE) vial caps, aluminum foil, glass disposable pipettes, filters,
and other apparatus that release fluorinated compounds. All supplies and reagents
should be verified prior to use. If found, measures should be taken to remove the
contamination, if possible, or find other suppliers or materials to use that meet method or
project criteria.
B4.3.3 Polyethylene disposable pipettes are recommended. Alternate
materials may be used if the blank criteria in the determinative method are met. When a
new batch of disposable pipettes is received, at least one should be checked for release
of target analytes or interferences.
B4.3.4 If labware is re-used, the procedure described for labware cleaning
(Sec. A6.4) should be followed to minimize risk of contamination. The blank criteria in
Sec. 9.5 of Method 8327 can be used as a guideline for evaluating cleanliness.
B5.0 SAFETY
B5.1 This method does not address all safety issues associated with its use. The
laboratory is responsible for maintaining a safe work environment and a current awareness file
of U.S. Occupational Safety and Health Administration (OSHA) regulations regarding the safe
handling of the chemicals specified in this method. A reference file of safety data sheets
(SDSs) must be available to all personnel involved in these analyses.
B5.2 Users of this method should operate a formal safety program.
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B5.3 The toxicity and carcinogenicity of each reagent used in this method has not
been precisely defined; however, each chemical compound is treated as a health hazard.
Exposure to these chemicals should be reduced to the lowest possible level and the appropriate
personal protective equipment (PPE) should be utilized. Review SDSs for specific physical and
health hazards including appropriate PPE to be used. SDSs may be accessed at multiple
locations (e.g., www.siqmaaldrich.com,www.well-labs.com, and www.isotope.com).
B6.0 EQUIPMENT AND SUPPLIES
The mention of trade names or commercial products in this method is for illustrative
purposes only and does not constitute an EPA endorsement or exclusive recommendation for
use. The products and instrument settings cited in SW-846 methods represent those products
and settings used during method development or subsequently evaluated by the Agency.
Glassware, reagents, supplies, equipment, and settings other than those listed in this
manual may be employed provided that method performance appropriate for the intended
application has been demonstrated and documented. This section does not list all common
laboratory containers (e.g., beakers and flasks) that might be used.
B6.1	Adjustable volume pipettes, 10-|jL, 20-|jL, 100-|jL, 200-|jL, and 1000-|jL, 5 ml_,
and 10 mL.
B6.2	Analytical balance, capable of weighing to 0.01 g
B6.3	Miscellaneous Supplies
B6.3.1 10- to 25 mL filter-adaptable HDPE, polypropylene, or glass syringe
with luer lock (rubber tipped plungers are not to be used).
B6.3.2 50 mL polypropylene tubes (BD Falcon, Catalog # 352098)
B6.3.3 15 mL polypropylene tubes (BD Falcon, Catalog # 352097); use
pre-weighed tubes for collection of field samples and field QC
B6.3.4 Polyethylene disposable pipettes (SEDI-PETTM PI PET, Source -
Samco Scientific, part no. 252)
B6.3.5 Pipette tips: polypropylene pipette tips of various sizes (Eppendorf,
catalogue #s 022491997, 022492080, 022491954, 022491946, and 022491512)
B6.3.6 Acrodisc GxF/0.2|jm GHP or equivalent membrane syringe driven
filter unit. Filters must be cleaned prior to use. A suggested protocol is to rinse each
filter with 2 x10 mL acetonitrile and then 2 x10 mL methanol prior to use. Other protocols
may be appropriate if PFAS contamination is removed or reduced to levels appropriate
for the project.
B6.4 Labware cleaning instructions - If labware is reused it should be washed in hot
water with detergent such as powdered Alconox, Deto-Jet, Luminox, or Citrojet, rinsed in hot
water and rinsed with distilled water. Rinse with organic solvents such as acetone, methanol,
and/or acetonitrile.
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B7.0 REAGENTS AND STANDARDS
B7.1 Reagent-grade or pesticide grade chemicals, at a minimum, should be used in all
tests. Unless otherwise indicated, all reagents should conform to the specifications of the
Committee on Analytical Reagents of the American Chemical Society, where specifications are
available. Other grades may be used, provided the reagent is of sufficiently high purity to permit
its use without lessening the accuracy of the determination.
B7.2 Reagent water. All references to water in this method refer to organic-free
reagent water as defined in SW-846 Chapter One. Reagent water from in-house Dl systems will
likely require additional polishing with a point-of-use water purification system to meet method
requirements. The laboratory should check for PFAS contamination coming from the point-of-
use system (it should not contain fluoropolymers, where practical). Some bottled HPLC water
has been shown to contain PFAS.
B7.3 Reagents: Items shown are for informational purpose only; equivalent reagents
and standards may be used. All reagents and solvents should be of pesticide residue purity or
higher to minimize interference problems, preferably LC/MS grade or equivalent.
B7.3.1 Methanol, CH30H (CAS RN 67-56-1)
B7.3.2 Acetic acid, CH3COOH (CAS RN 64-19-7)
B7.3.3 50:50 Methanol-reagent water containing 0.1 % acetic acid
B7.3.4 See determinative method for surrogate, internal standard, and
target spiking solutions.
B8.0 SAMPLE COLLECTION, PRESERVATION, AND STORAGE
See introductory material to SW-846 Chapter Four, "Organic Analytes", Method 3500,
and the specific determinative method to be used.
B9.0 QUALITY CONTROL
B9.1 Refer to SW-846 Chapter One for guidance on quality assurance (QA) and quality
control (QC) protocols. When inconsistencies exist between QC guidelines, method-specific QC
criteria take precedence over both technique-specific criteria and the criteria given in Chapter
One, and technique-specific QC criteria take precedence over the criteria in Chapter One. Any
effort involving the collection of analytical data should include development of a structured and
systematic planning document, such as a Quality Assurance Project Plan (QAPP) or a Sampling
and Analysis Plan (SAP), which translates project objectives and specifications into directions for
those that will implement the project and assess the results. Each laboratory should maintain a
formal quality assurance program. The laboratory should also maintain records to document the
quality of the data generated. All data sheets and quality control data should be maintained for
reference or inspection.
B9.2 See Sec. 9 of Methods 8327 and 8328 for QA/QC requirements specific to that
analysis.
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B9.3 Initial demonstration of proficiency and lower limit of quantitation (LLOQ)
B9.3.1 Each laboratory must demonstrate initial proficiency with each
sample preparation and determinative method combination it utilizes by generating data
of acceptable accuracy and precision for target analytes in a clean matrix. The
laboratory must also repeat the demonstration of proficiency whenever new staff
members are trained or significant changes in instrumentation are made. See Method
8000D, Sec. 9.3 for information on how to accomplish a demonstration of proficiency.
B9.3.2 The laboratory should verify the LLOQ initially and in each
preparation batch using clean control material (e.g., reagent water) or a representative
sample matrix, free of target compounds. See Sec. 9.9 of Method 8327 or Method 8328
for establishing the LLOQ level and for the acceptance criteria to use.
B9.4 Blanks - Before processing any samples, the analyst should demonstrate that all
parts of the equipment in contact with the sample and reagents are interference-free. This is
accomplished through the preparation and analysis of method blanks (MBs). Each time samples
are prepared, and when there is a change in reagents, an MB should be prepared and analyzed
for the compounds of interest as a safeguard against chronic laboratory contamination.
B9.4.1 At least one MB for every 20 field samples must be prepared in
reagent water to investigate for PFAS contamination throughout sample preparation and
analysis. Method blanks are subjected to all steps in Sec. B11.0.
B9.4.2 Because PFAS contamination is common in reagents, a RB should
be prepared with each batch of samples using 50:50 methanol-water solution containing
0.1% acetic acid to investigate for system/laboratory contamination
B9.5 Laboratory Controls - Each preparation batch of twenty or fewer samples should
also include a laboratory control sample (LCS), a matrix spike sample (MS), a matrix spike
duplicate (MSD) or laboratory duplicate sample (if sufficient volume is available), and an LLOQ
verification.
B9.6 Any method blanks, LCSs, MS/MSDs, duplicate samples and LLOQ verifications
should be subjected to the same preparation procedures (Sec. B11.0) as those used on actual
samples.
B9.7 All field and QC samples should be spiked with an appropriate concentration of
mass labelled PFAS isotopes, whether used as surrogates or internal standards, as a check on
the preparation procedure or to report recovery-corrected concentrations of target analytes.
B10.0 CALIBRATION AND STANDARDIZATION
There are no calibration or standardization steps directly associated with this preparation
procedure.
B11.0 PROCEDURE
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B11.1 Sample preparation - Each batch of samples (20 or fewer) should contain a MB,
LCS, MS, sample duplicate or MSD (if available), and an LLOQ verification sample. The
following sections refer to Method 8327 for suggested standard addition concentrations for
PFAS target analytes and associated surrogates by QC sample type. Different concentrations
may be spiked depending on the needs of the project, the sensitivity of the instrument, or the
determinative method used. The analyst should strive to keep the total spike additions to <1%
of the final volume (<100 uL in 10 ml_) to minimize errors in the dilution.
B11.1.1 Weigh all field collected samples in the 15 ml_ polypropylene
centrifuge tubes prior to any preparation steps and calculate the difference weight using
the value of the pre-weighed container. Use a difference weight, assuming a density of
1.0 g/mL, to determine volume. This volume will be used to determine amount of solvent
to add if significantly different than 5 mL.
NOTE: If pre-weighed containers were not used to collect samples, mark the level of the
sample on the outside of the container for determination of the volume. Certified
graduation marks on sample containers may also be used to estimate sample
volume.
B11.1.2 MB - Prepare by adding 5.0 ml_ of reagent water to a 15 mL
polypropylene tube and adding an appropriate volume of the surrogate/internal standard
spiking solution (Sec. 7.4.1 of Method 8327).
B11.1.3 LCS - Prepare by adding 5.0 ml_ of reagent water to a 15 mL
polypropylene tube and adding appropriate volumes of the surrogate/internal standard
spiking solution (Sec. 7.4.1 of Method 8327) and MS/MSD and LCS target compounds
spiking solution (Sec. 7.4.2 of Method 8327).
NOTE: If field samples were collected at a different volume, measure a similar
volume for MB and LCS into a similarly sized container.
B11.1.4 LLOQ Verification Sample - Prepare by adding 5 mL of reagent
water to a 15 mL polypropylene tube and adding appropriate volumes of the
surrogate/internal standard spiking solution (Sec. 7.4.1 of Method 8327) and LLOQ
verification spiking solution (Sec. 7.4.3 of Method 8327). Prepare additional LLOQ
verification samples at higher concentration as needed (Sec. 7.4.3 of Method 8327).
B11.1.5 Sample - Allow the 5 mL sample collected in a 15 mL polypropylene
tube to warm to room and weigh. Spike with an appropriate volume of the surrogate
/internal standard spiking solution (Sec. 7.4.1 of Method 8327).
NOTE: Different volumes may be received by the laboratory and the entire volume, as
received, must be prepared. Removing aliquots from a sample (volumes less
than entire container) prior to solvent addition is not recommended prior to
addition of MeOH, because longer chain PFAS are known to sorb to container
walls in water samples unless >50% organic cosolvent is present.
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NOTE: If the original container has inadequate volume to hold a 1:1 dilution (i.e. lacking
sufficient volume to add the same volume of methanol), the sample may be
transferred to a larger container, but the interior of the original sample container
must be solvent rinsed, and this rinse must be incorporated into the solvent
dilution of the sample (Sec. B11.2). Hand shake or vortex the rinse solvent in the
original sample container for ~2 min to ensure quantitative transfer.
B11.1.6 MS/MSD or MS/sample duplicate - Use separately collected
containers for the MS, MSD and/or duplicate QC samples, provided sufficient sample is
available. Add an appropriate volume of the surrogate/internal standard spiking solution
(Sec. 7.4.1 of Method 8327) to each of these QC samples, and add an appropriate
volume of the MS/MSD and LCS target compounds spiking solution (Sec. 7.4.2 of
Method 8327) to MS/MSD samples.
B11.2 Sample Dilution
B11.2.1 For field collected samples, matrix spikes, matrix spike duplicates
and sample duplicates, add 5 ml_ methanol to each tube. If sample volumes differ from 5
ml_ by >5%, (i.e. <4.75 ml_ or >5.25ml_), adjust the methanol volume added according to
the volume determined in B11.1.1. This may also require the adjustment of the amount
of surrogates/internal standard and the amount of target compounds spikes added, if
applicable.
NOTE: Adjusting the surrogates and target compounds standard additions for alternate
sample volumes can be accomplished by adding surrogates (and target
compounds, as applicable) to the methanol used for dilution. For example, field
samples, duplicates, and method blanks can be prepared with methanol spiked
with surrogates/internal standards at concentrations of 160 ng/L, which would
result in surrogate concentrations of 80 ng/L in the samples after 1:1 dilution with
methanol. Similarly, LCS and MS/MSD samples can be prepared with methanol
that has been spiked with surrogates/internal standards and targets compounds
both at concentrations of 160 ng/L (nom.), which would result in surrogate and
target analyte concentrations of 80 ng/L in the samples after 1:1 dilution with
methanol. For sample volumes <4.75 mL or >5.25 mL, add the same volume of
methanol solution as was calculated for the sample in Sec. B11.1.1.
B11.2.2 For blanks, LCS, and LLOQ verification QC samples prepared in 5
mL reagent water, add 5 mL of methanol. If alternate sample volumes are prepared as
described in B11.2.1, add surrogates and target compounds (as applicable) in the same
manner as was done for field samples and MS/MSD (as spiking solutions or added to
the methanol used as a dilution solvent, as appropriate).
B11.2.3 Hand shake or vortex for ~2 min.
B11.2.4 Filter each diluted field sample and associated QC sample through
separate rinsed Acrodisc GxF/0.2|jm GHP membrane syringe-driven filters (See Sec.
6.3.8 of Method 8327) to remove particulates in the samples.
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B11.2.5 Add acetic acid to all samples to adjust to pH ~3 - 4 after filtration
(e.g., add 10|jL of glacial acetic acid to 10ml_). Transfer approximately 1 ml_ of that
solution to an LC vial and apply a polyethylene cap. The sample is now ready for
analysis.
B11.2.6 The final volume of the solution is 10 ml_ for laboratory-prepared QC
samples. The final volume for field samples and QC is calculated summing the sample
and added methanol volumes.
NOTE: To minimize PFAS contamination in subsequent samples, it is recommended to
soak reusable syringes in hot tap water and then rinse with 5 X 10 ml_ reagent
water, 3 X 10 ml_ acetonitrile and 3 x 10 ml_ methanol.
B12.0 DATA ANALYSIS AND CALCULATIONS
There are no data analysis and calculation steps directly associated with this procedure.
Follow the directions given in the determinative method.
B13.0 METHOD PERFORMANCE
B13.1 Performance data and related information are provided in SW-846 methods only
as examples and guidance. The data do not represent required performance goals for users of
the methods. Instead, performance criteria should be developed on a project-specific basis, and
the laboratory should establish in-house QC performance criteria for the application of this
method.
B13.2 TBD
B14.0 POLLUTION PREVENTION
B14.1 Pollution prevention encompasses any technique that reduces or eliminates the
quantity and/or toxicity of waste at the point of generation. Numerous opportunities for pollution
prevention exist in laboratory operations. The EPA has established a preferred hierarchy of
environmental management techniques that places pollution prevention as the management
option of first choice. Whenever feasible, laboratory personnel should use pollution prevention
techniques to address their waste generation. When wastes cannot be feasibly reduced at the
source, the Agency recommends recycling as the next best option.
B14.2 For information about pollution prevention that may be applicable to laboratories
and research institutions consult Less is Better: Laboratory Chemical Management for Waste
Reduction, a free publication available from the American Chemical Society (ACS), Committee on
Chemical Safety, http://portal.acs.Org/portal/fileFetch/C/WPCP_012290/pdf/WPCP_012290.pdf.
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B15.0 WASTE MANAGEMENT
The Environmental Protection Agency requires that laboratory waste management
practices be conducted consistent with all applicable rules and regulations. The Agency urges
laboratories to protect the air, water, and land by minimizing and controlling all releases from
hoods and bench operations, complying with the letter and spirit of any sewer discharge permits
and regulations, and by complying with all solid and hazardous waste regulations, particularly
the hazardous waste identification rules and land disposal restrictions. For further information on
waste management, consult The Waste Management Manual for Laboratory Personnel
available from the American Chemical Society at the address listed in Sec. B14.2.
B16.0 REFERENCES
1.	U.S. Environmental Protection Agency, Region 5 Laboratory, "Standard
Operating Procedure for the Analysis of Polyfluorinated Compounds of Interest to OSRTI in
Water, Sludge, Influent, Effluent, and Wastewater by Multiple Reaction Monitoring Liquid
Chromatography/Mass Spectrometry (LC/MS/MS)," 75 pp., 2016.
2.	Standard Practices for Sampling Water, American Society for Testing and
Materials, Philadelphia. ASTM Annual Book Standards, Part 31, D3370-76.
B17.0 TABLES, DIAGRAMS, FLOWCHARTS, AND VALIDATION
DATA TBD
8327- 58
Revision 0
June 2019

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